patch 9.1.0126: Internal error when using upper-case mark in getregion()

Problem:  Internal error when passing mark in another buffer to
          getregion().
Solution: Don't allow marks in another buffer (zeertzjq)

closes: #14076

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Internal error when passing mark in another buffer to getregion()
diff --git a/src/version.c b/src/version.c
index f4b2a1e..b8e79dd 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    126,
+/**/
     125,
 /**/
     124,