patch 9.1.0831: 'findexpr' can't be used as lambad or Funcref

Problem:  'findexpr' can't be used for lambads
          (Justin Keyes)
Solution: Replace the findexpr option with the findfunc option
          (Yegappan Lakshmanan)

related: #15905
closes: #15976

Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/structs.h b/src/structs.h
index 33367f0..47999a9 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -3248,6 +3248,8 @@
 #ifdef FEAT_EVAL
     char_u	*b_p_tfu;	// 'tagfunc' option value
     callback_T	b_tfu_cb;	// 'tagfunc' callback
+    char_u	*b_p_ffu;	// 'findfunc' option value
+    callback_T	b_ffu_cb;	// 'findfunc' callback
 #endif
     int		b_p_eof;	// 'endoffile'
     int		b_p_eol;	// 'endofline'
@@ -3334,9 +3336,6 @@
     char_u	*b_p_efm;	// 'errorformat' local value
 #endif
     char_u	*b_p_ep;	// 'equalprg' local value
-#ifdef FEAT_EVAL
-    char_u	*b_p_fexpr;	// 'findexpr' local value
-#endif
     char_u	*b_p_path;	// 'path' local value
     int		b_p_ar;		// 'autoread' local value
     char_u	*b_p_tags;	// 'tags' local value