patch 8.0.1046: code duplication in diff mode

Problem:    Code duplication in diff mode.
Solution:   Use diff_equal_char() also in diff_cmp(). (Rick Howe)
diff --git a/src/version.c b/src/version.c
index b1e2d5a..a57e11f 100644
--- a/src/version.c
+++ b/src/version.c
@@ -770,6 +770,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1046,
+/**/
     1045,
 /**/
     1044,