patch 8.0.0452: some macros are in lower case

Problem:    Some macros are in lower case.
Solution:   Make a few more macros upper case.
diff --git a/src/message.c b/src/message.c
index 06f8cb9..5379b5b 100644
--- a/src/message.c
+++ b/src/message.c
@@ -1789,7 +1789,7 @@
     if (list && lcs_trail)
     {
 	trail = s + STRLEN(s);
-	while (trail > s && vim_iswhite(trail[-1]))
+	while (trail > s && VIM_ISWHITE(trail[-1]))
 	    --trail;
     }