checkpatch: Test SYMBOLIC_PERMS multiple times per line

There are occasions where symbolic perms are used in a ternary like

		return (channel == 0) ? S_IRUGO | S_IWUSR : S_IRUGO;

The current test will find the first use "S_IRUGO | S_IWUSR" but not the second use "S_IRUGO" on the same line.

Improve the test to look for all instances on a line.

---
 scripts/checkpatch.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 5fe361e1ed5e..d2464002bb40 100755
@@ -6429,7 +6429,7 @@ sub process {
 		}
 
 # check for uses of S_<PERMS> that could be octal for readability
-		if ($line =~ /\b($multi_mode_perms_string_search)\b/) {
+		while ($line =~ m{\b($multi_mode_perms_string_search)\b}g) {
 			my $oval = $1;
 			my $octal = perms_to_octal($oval);
 			if (WARN("SYMBOLIC_PERMS",