patch 8.2.1978: making a mapping work in all modes is complicated

Problem:    Making a mapping work in all modes is complicated.
Solution:   Add the <Cmd> special key. (Yegappan Lakshmanan, closes #7282,
            closes 4784, based on patch by Bjorn Linse)
diff --git a/src/map.c b/src/map.c
index b46ba37..229095b 100644
--- a/src/map.c
+++ b/src/map.c
@@ -1639,8 +1639,7 @@
  * Returns NULL when out of memory.
  */
     char_u *
-vim_strsave_escape_csi(
-    char_u *p)
+vim_strsave_escape_csi(char_u *p)
 {
     char_u	*res;
     char_u	*s, *d;