checkpatch.pl: also suggest 'else if' when if follows brace

This might help a kernel hacker think twice before blindly adding a
newline.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -3621,7 +3621,7 @@ sub process {
 # if should not continue a brace
 		if ($line =~ /}\s*if\b/) {
 			ERROR("TRAILING_STATEMENTS",
-			      "trailing statements should be on next line\n" .
+			      "trailing statements should be on next line (or did you mean 'else if'?)\n" .
 				$herecurr);
 		}
 # case and default should not have general statements after them