patch 8.0.1056: cannot build with +diff but without +multi_byte

Problem:    Cannot build with the diff feature but without the mutli-byte
            feature.
Solution:   Remove #ifdefs. (John Marriott)

src/version.c

@@ -769,6 +769,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1056,
 /**/
     1055,
 /**/