patch 8.2.4911: the mode #defines are not clearly named

Problem:    The mode #defines are not clearly named.
Solution:   Prepend MODE_.  Renumber them to put the mapped modes first.
diff --git a/src/gui.c b/src/gui.c
index 2d59ea2..2544c53 100644
--- a/src/gui.c
+++ b/src/gui.c
@@ -1207,7 +1207,7 @@
 	else
 #endif
 	    shape = &shape_table[get_shape_idx(FALSE)];
-	if (State & LANGMAP)
+	if (State & MODE_LANGMAP)
 	    id = shape->id_lm;
 	else
 	    id = shape->id;
@@ -1580,7 +1580,7 @@
      * At the "more" and ":confirm" prompt there is no redraw, put the cursor
      * at the last line here (why does it have to be one row too low?).
      */
-    if (State == ASKMORE || State == CONFIRM)
+    if (State == MODE_ASKMORE || State == MODE_CONFIRM)
 	gui.row = gui.num_rows;
 
     // Only comparing Rows and Columns may be sufficient, but let's stay on
@@ -3192,22 +3192,23 @@
     // Determine which mouse settings to look for based on the current mode
     switch (get_real_state())
     {
-	case NORMAL_BUSY:
-	case OP_PENDING:
+	case MODE_NORMAL_BUSY:
+	case MODE_OP_PENDING:
 # ifdef FEAT_TERMINAL
-	case TERMINAL:
+	case MODE_TERMINAL:
 # endif
-	case NORMAL:		checkfor = MOUSE_NORMAL;	break;
-	case VISUAL:		checkfor = MOUSE_VISUAL;	break;
-	case SELECTMODE:	checkfor = MOUSE_VISUAL;	break;
-	case REPLACE:
-	case REPLACE+LANGMAP:
-	case VREPLACE:
-	case VREPLACE+LANGMAP:
-	case INSERT:
-	case INSERT+LANGMAP:	checkfor = MOUSE_INSERT;	break;
-	case ASKMORE:
-	case HITRETURN:		// At the more- and hit-enter prompt pass the
+	case MODE_NORMAL:	checkfor = MOUSE_NORMAL; break;
+	case MODE_VISUAL:	checkfor = MOUSE_VISUAL; break;
+	case MODE_SELECT:	checkfor = MOUSE_VISUAL; break;
+	case MODE_REPLACE:
+	case MODE_REPLACE | MODE_LANGMAP:
+	case MODE_VREPLACE:
+	case MODE_VREPLACE | MODE_LANGMAP:
+	case MODE_INSERT:
+	case MODE_INSERT | MODE_LANGMAP:
+				checkfor = MOUSE_INSERT; break;
+	case MODE_ASKMORE:
+	case MODE_HITRETURN:	// At the more- and hit-enter prompt pass the
 				// mouse event for a click on or below the
 				// message line.
 				if (Y_2_ROW(y) >= msg_row)
@@ -3220,8 +3221,8 @@
 	     * On the command line, use the clipboard selection on all lines
 	     * but the command line.  But not when pasting.
 	     */
-	case CMDLINE:
-	case CMDLINE+LANGMAP:
+	case MODE_CMDLINE:
+	case MODE_CMDLINE | MODE_LANGMAP:
 	    if (Y_2_ROW(y) < cmdline_row && button != MOUSE_MIDDLE)
 		checkfor = MOUSE_NONE;
 	    else
@@ -3238,7 +3239,8 @@
      * modes.  Don't do this when dragging the status line, or extending a
      * Visual selection.
      */
-    if ((State == NORMAL || State == NORMAL_BUSY || (State & INSERT))
+    if ((State == MODE_NORMAL || State == MODE_NORMAL_BUSY
+						      || (State & MODE_INSERT))
 	    && Y_2_ROW(y) >= topframe->fr_height + firstwin->w_winrow
 	    && button != MOUSE_DRAG
 # ifdef FEAT_MOUSESHAPE
@@ -3270,7 +3272,7 @@
     if (!mouse_has(checkfor) || checkfor == MOUSE_COMMAND)
     {
 	// Don't do modeless selection in Visual mode.
-	if (checkfor != MOUSE_NONEF && VIsual_active && (State & NORMAL))
+	if (checkfor != MOUSE_NONEF && VIsual_active && (State & MODE_NORMAL))
 	    return;
 
 	/*
@@ -3291,7 +3293,7 @@
 	{
 	    if (clip_star.state == SELECT_CLEARED)
 	    {
-		if (State & CMDLINE)
+		if (State & MODE_CMDLINE)
 		{
 		    col = msg_col;
 		    row = msg_row;
@@ -4086,17 +4088,17 @@
 #ifdef USE_ON_FLY_SCROLL
 	current_scrollbar = sb_num;
 	scrollbar_value = value;
-	if (State & NORMAL)
+	if (State & MODE_NORMAL)
 	{
 	    gui_do_scroll();
 	    setcursor();
 	}
-	else if (State & INSERT)
+	else if (State & MODE_INSERT)
 	{
 	    ins_scroll();
 	    setcursor();
 	}
-	else if (State & CMDLINE)
+	else if (State & MODE_CMDLINE)
 	{
 	    if (msg_scrolled == 0)
 	    {
@@ -4131,11 +4133,11 @@
 #ifdef USE_ON_FLY_SCROLL
 	scrollbar_value = value;
 
-	if (State & NORMAL)
+	if (State & MODE_NORMAL)
 	    gui_do_horiz_scroll(scrollbar_value, FALSE);
-	else if (State & INSERT)
+	else if (State & MODE_INSERT)
 	    ins_horscroll();
-	else if (State & CMDLINE)
+	else if (State & MODE_CMDLINE)
 	{
 	    if (msg_scrolled == 0)
 	    {
@@ -4890,8 +4892,8 @@
     // Only handle this when 'mousefocus' set and ...
     if (p_mousef
 	    && !hold_gui_events		// not holding events
-	    && (State & (NORMAL|INSERT))// Normal/Visual/Insert mode
-	    && State != HITRETURN	// but not hit-return prompt
+	    && (State & (MODE_NORMAL | MODE_INSERT))// Normal/Visual/Insert mode
+	    && State != MODE_HITRETURN	// but not hit-return prompt
 	    && msg_scrolled == 0	// no scrolled message
 	    && !need_mouse_correct	// not moving the pointer
 	    && gui.in_focus)		// gvim in focus
@@ -5022,7 +5024,7 @@
     if (wp == NULL)
 	return NULL;
 #ifdef FEAT_MOUSESHAPE
-    if (State == HITRETURN || State == ASKMORE)
+    if (State == MODE_HITRETURN || State == MODE_ASKMORE)
     {
 	if (Y_2_ROW(y) >= msg_row)
 	    update_mouseshape(SHAPE_IDX_MOREL);
@@ -5031,10 +5033,10 @@
     }
     else if (row > wp->w_height)	// below status line
 	update_mouseshape(SHAPE_IDX_CLINE);
-    else if (!(State & CMDLINE) && wp->w_vsep_width > 0 && col == wp->w_width
+    else if (!(State & MODE_CMDLINE) && wp->w_vsep_width > 0 && col == wp->w_width
 	    && (row != wp->w_height || !stl_connected(wp)) && msg_scrolled == 0)
 	update_mouseshape(SHAPE_IDX_VSEP);
-    else if (!(State & CMDLINE) && wp->w_status_height > 0
+    else if (!(State & MODE_CMDLINE) && wp->w_status_height > 0
 				  && row == wp->w_height && msg_scrolled == 0)
 	update_mouseshape(SHAPE_IDX_STATUS);
     else
@@ -5454,7 +5456,7 @@
     // syntax HL if we were busy redrawing.
     did_emsg = save_did_emsg;
 
-    if (State & (NORMAL | INSERT))
+    if (State & (MODE_NORMAL | MODE_INSERT))
     {
 	gui_update_screen();		// update the screen
 	msg_didout = 0;			// overwrite any message
@@ -5558,7 +5560,7 @@
      * When the cursor is at the command line, add the file names to the
      * command line, don't edit the files.
      */
-    if (State & CMDLINE)
+    if (State & MODE_CMDLINE)
     {
 	shorten_filenames(fnames, count);
 	for (i = 0; i < count; ++i)