patch 9.1.0147: Cannot keep a buffer focused in a window

Problem:  Cannot keep a buffer focused in a window
          (Amit Levy)
Solution: Add the 'winfixbuf' window-local option
          (Colin Kennedy)

fixes:  #6445
closes: #13903

Signed-off-by: Colin Kennedy <colinvfx@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/option.c b/src/option.c
index dd3542f..8123a2a 100644
--- a/src/option.c
+++ b/src/option.c
@@ -6420,6 +6420,7 @@
 #ifdef FEAT_LINEBREAK
 	case PV_NUW:	return (char_u *)&(curwin->w_p_nuw);
 #endif
+	case PV_WFB:	return (char_u *)&(curwin->w_p_wfb);
 	case PV_WFH:	return (char_u *)&(curwin->w_p_wfh);
 	case PV_WFW:	return (char_u *)&(curwin->w_p_wfw);
 #if defined(FEAT_QUICKFIX)