patch 8.0.0946: using PATH_MAX does not work well on some systems

Problem:    Using PATH_MAX does not work well on some systems.
Solution:   use MAXPATHL instead. (James McCoy, closes #1973)

src/version.c

@@ -769,6 +769,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    946,
 /**/
     945,
 /**/