checkpatch: Eliminate false positive in case of comma-space-square bracket

Previously, an error was printed in cases such as:
{ [1] = 5, [2] = 6 }
The space passed OK after a curly brace, but not after a comma.
Now, a space before a square bracket is allowed, if a comma comes before
it.
Signed-off-by: NLeonid Bloch <leonid@daynix.com>
Message-Id: <1446112118-12376-2-git-send-email-leonid@daynix.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

scripts/checkpatch.pl

@@ -1715,11 +1715,13 @@ sub process {
 #  1. with a type on the left -- int [] a;
 #  2. at the beginning of a line for slice initialisers -- [0...10] = 5,
 #  3. inside a curly brace -- = { [0...10] = 5 }
+#  4. after a comma -- [1] = 5, [2] = 6
 		while ($line =~ /(.*?\s)\[/g) {
 			my ($where, $prefix) = ($-[1], $1);
 			if ($prefix !~ /$Type\s+$/ &&
 			    ($where != 0 || $prefix !~ /^.\s+$/) &&
-			    $prefix !~ /{\s+$/) {
+			    $prefix !~ /{\s+$/ &&
+			    $prefix !~ /,\s+$/) {
 				ERROR("space prohibited before open square bracket '['\n" . $herecurr);
 			}
 		}