patch 7.4.1631

Problem:    Compiler doesn't understand switch on all enum values. (Tony
            Mechelynck)
Solution:   Initialize variable.

src/channel.c

@@ -2100,7 +2100,7 @@ channel_part_info(channel_T *channel, dict_T *dict, char *name, int part)
     chanpart_T *chanpart = &channel->ch_part[part];
     char	namebuf[20];
     size_t	tail;
-    char	*s;
+    char	*s = "";
 
     STRCPY(namebuf, name);
     STRCAT(namebuf, "_");

src/version.c

@@ -748,6 +748,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1631,
 /**/
     1630,
 /**/