patch 9.1.1394: tabpanel not correctly redrawn on tabonly

Problem:  tabpanel not correctly redrawn on tabonly
          (Maxim Kim, after v9.1.1391)
Solution: force redraw of the tabpanel, tweak style
          (Hirohito Higashi)

fixes: #17322
closes: #17330

Signed-off-by: Hirohito Higashi <h.east.727@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/proto/tabpanel.pro b/src/proto/tabpanel.pro
index 3cbaa2f..34c3e52 100644
--- a/src/proto/tabpanel.pro
+++ b/src/proto/tabpanel.pro
@@ -1,6 +1,6 @@
 /* tabpanel.c */
 int tabpanel_width(void);
-int tabpanel_leftcol(win_T	*wp);
+int tabpanel_leftcol(win_T *wp);
 int tabpanelopt_changed(void);
 void draw_tabpanel(void);
 int get_tabpagenr_on_tabpanel(void);