patch 8.0.1496: clearing a pointer takes two lines

Problem:    Clearing a pointer takes two lines.
Solution:   Add VIM_CLEAR() and replace vim_clear(). (Hirohito Higashi,
            closes #2629)
diff --git a/src/term.c b/src/term.c
index 6303e10..1f17d9f 100644
--- a/src/term.c
+++ b/src/term.c
@@ -2502,7 +2502,8 @@
 }
 
 /*
- * out_flush_cursor(): flush the output buffer and redraw the cursor
+ * out_flush_cursor(): flush the output buffer and redraw the cursor.
+ * Does not flush recursively in the GUI to avoid slow drawing.
  */
     void
 out_flush_cursor(
@@ -3912,8 +3913,7 @@
 {
     while (tc_len > 0)
 	vim_free(termcodes[--tc_len].code);
-    vim_free(termcodes);
-    termcodes = NULL;
+    VIM_CLEAR(termcodes);
     tc_max_len = 0;
 
 #ifdef HAVE_TGETENT
@@ -5648,7 +5648,7 @@
 	    /* Work out our pseudo mouse event. Note that MOUSE_RELEASE gets
 	     * added, then it's not mouse up/down. */
 	    key_name[0] = (int)KS_EXTRA;
-            if (wheel_code != 0
+	    if (wheel_code != 0
 			      && (wheel_code & MOUSE_RELEASE) != MOUSE_RELEASE)
 	    {
 		if (wheel_code & MOUSE_CTRL)