patch 9.0.1759: Visual highlight not working with cursor at end of screen line

Problem:  Visual highlight not working with cursor at end of screen line
          and 'showbreak'.
Solution: Only update "vcol_prev" when drawing buffer text.

closes: #12865

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>
diff --git a/src/drawline.c b/src/drawline.c
index 0be0718..88d72ce 100644
--- a/src/drawline.c
+++ b/src/drawline.c
@@ -3792,9 +3792,11 @@
 	}
 #endif
 
+	if (wlv.draw_state == WL_LINE)
+	    vcol_prev = wlv.vcol;
+
 	// Store character to be displayed.
 	// Skip characters that are left of the screen for 'nowrap'.
-	vcol_prev = wlv.vcol;
 	if (wlv.draw_state < WL_LINE || n_skip <= 0)
 	{
 	    // Store the character.