patch 9.0.0206: redraw flags are not named specifically

Problem:    Redraw flags are not named specifically.
Solution:   Prefix "UPD_" to the flags, for UPDate_screen().
diff --git a/src/indent.c b/src/indent.c
index 90ad5e2..d941abc 100644
--- a/src/indent.c
+++ b/src/indent.c
@@ -1132,7 +1132,7 @@
 		oap->is_VIsual ? start_lnum + oap->line_count :
 		last_changed + 1, 0L);
     else if (oap->is_VIsual)
-	redraw_curbuf_later(INVERTED);
+	redraw_curbuf_later(UPD_INVERTED);
 
     if (oap->line_count > p_report)
     {
@@ -1830,10 +1830,10 @@
 	&& tabstop_eq(curbuf->b_p_vts_array, new_vts_array))
 	; // not changed
     else
-	redraw_curbuf_later(NOT_VALID);
+	redraw_curbuf_later(UPD_NOT_VALID);
 #else
     if (curbuf->b_p_ts != new_ts)
-	redraw_curbuf_later(NOT_VALID);
+	redraw_curbuf_later(UPD_NOT_VALID);
 #endif
     if (first_line != 0)
 	changed_lines(first_line, 0, last_line + 1, 0L);