patch 9.0.0160: some diff mode tests fail

Problem:    Some diff mode tests fail.
Solution:   Only advance "ptr" when a text property follows.
diff --git a/src/version.c b/src/version.c
index 813ff63..a4cafbd 100644
--- a/src/version.c
+++ b/src/version.c
@@ -736,6 +736,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    160,
+/**/
     159,
 /**/
     158,