patch 8.2.4555: getmousepos() returns the wrong column

Problem:    getmousepos() returns the wrong column. (Ernie Rael)
Solution:   Limit to the text size, not the number of bytes.
diff --git a/src/version.c b/src/version.c
index bdd9dd8..20b5a03 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4555,
+/**/
     4554,
 /**/
     4553,