top: fix regression created when fields mgmt reorg'd

When the calibrate_fields function was broken up for
mainainability, an obscure regression was introduced.

For the resulting bug to affect the display, all of
the following conditions would have to be met:
 . USE_X_COLHDR was not defined
 . column highlighting had been turned on
 . many, perhaps all, fields were displayable
 . the user then typed the <End> key
 . and the current sort column just happened to
   be immediately to the left of the left-most
   visible field

This patch corrects for that remote possibility.

Reference:
commit d0e16acf15

Signed-off-by: Jim Warner <james.warner@comcast.net>

top/top.c

@@ -1538,6 +1538,9 @@ static void calibrate_fields (void) {
             s = scat(s, h);
             w->endpflg = i;
          }
+#ifndef USE_X_COLHDR
+         if (X_XOF == w->pflgsall[w->endpflg]) ++w->endpflg;
+#endif
       } // end: if (VIZISw(w))
 
       if (Rc.mode_altscr) w = w->next;