patch 7.4.1938

Problem:    When writing viminfo numbered marks were duplicated.
Solution:   Check for duplicates between current numbered marks and the ones
            read from viminfo.

src/version.c

@@ -753,6 +753,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1938,
 /**/
     1937,
 /**/