patch 7.4.1791

Problem:    Channel could be garbage collected too early.
Solution:   Don't free a channel or remove it from a job when it is still
            useful.

src/version.c

@@ -753,6 +753,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1791,
 /**/
     1790,
 /**/