patch 9.1.1461: tabpanel: tabpanel vanishes with popup menu

Problem:  tabpanel: tabpanel vanishes with popup menu
Solution: remove pum-related test in tabpanel_leftcol(), refactor a few
          related functions (Hirohito Higashi)

This commit does the following:
- Delete unnecessary pum-related checks in the tabpanel_leftcol()
  function
- remove pum-related check in tabpanel_leftcol()
- The argument of the TPL_LCOL() macro has been deleted.
- The argument of the tabpanel_leftcol() function has been changed
  to void
- The return type of the `win_comp_pos()` function has been changed to
  void

closes: #17549

Signed-off-by: Hirohito Higashi <h.east.727@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/tabpanel.c

@@ -137,12 +137,9 @@ tabpanel_width(void)
  * Return the offset of a window considering the width of tabpanel.
  */
     int
-tabpanel_leftcol(win_T *wp)
+tabpanel_leftcol(void)
 {
-    if (cmdline_pum_active() || (wp != NULL && WIN_IS_POPUP(wp)))
-	return 0;
-    else
-	return tpl_align == ALIGN_RIGHT ? 0 : tabpanel_width();
+    return tpl_align == ALIGN_RIGHT ? 0 : tabpanel_width();
 }
 
 /*