patch 8.1.0851: feedkeys() with "L" does not work properly

Problem:    feedkeys() with "L" does not work properly.
Solution:   Do not set typebuf_was_filled when using "L". (Ozaki Kiichi,
            closes #3885)

src/version.c

@@ -783,6 +783,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    851,
 /**/
     850,
 /**/