checkpatch: use $String consistently

String detection where a source line with a string constant is converted
can either have an X or a space.

Some of the string detection regexes do not allow the space character, but
there is a handy $String variable that does.

Convert the remaining uses of string detection regexes to use the $String
variable to reduce possible false negatives.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -1008,7 +1008,7 @@ sub sanitise_line {
 sub get_quoted_string {
 	my ($line, $rawline) = @_;
 
-	return "" if ($line !~ m/(\"[X\t]+\")/g);
+	return "" if ($line !~ m/($String)/g);
 	return substr($rawline, $-[0], $+[0] - $-[0]);
 }
 
@@ -4343,8 +4343,8 @@ sub process {
 			}
 
 			# Flatten any obvious string concatentation.
-			while ($dstat =~ s/("X*")\s*$Ident/$1/ ||
-			       $dstat =~ s/$Ident\s*("X*")/$1/)
+			while ($dstat =~ s/($String)\s*$Ident/$1/ ||
+			       $dstat =~ s/$Ident\s*($String)/$1/)
 			{
 			}
 
@@ -4625,7 +4625,7 @@ sub process {
 # to grep for the string.  Make exceptions when the previous string ends in a
 # newline (multiple lines in one string constant) or '\t', '\r', ';', or '{'
 # (common in inline assembly) or is a octal \123 or hexadecimal \xaf value
-		if ($line =~ /^\+\s*"[X\t]*"/ &&
+		if ($line =~ /^\+\s*$String/ &&
 		    $prevline =~ /"\s*$/ &&
 		    $prevrawline !~ /(?:\\(?:[ntr]|[0-7]{1,3}|x[0-9a-fA-F]{1,2})|;\s*|\{\s*)"\s*$/) {
 			if (WARN("SPLIT_STRING",
@@ -4671,13 +4671,13 @@ sub process {
 		}
 
 # concatenated string without spaces between elements
-		if ($line =~ /"X+"[A-Z_]+/ || $line =~ /[A-Z_]+"X+"/) {
+		if ($line =~ /$String[A-Z_]/ || $line =~ /[A-Za-z0-9_]$String/) {
 			CHK("CONCATENATED_STRING",
 			    "Concatenated strings should use spaces between elements\n" . $herecurr);
 		}
 
 # uncoalesced string fragments
-		if ($line =~ /"X*"\s*"/) {
+		if ($line =~ /$String\s*"/) {
 			WARN("STRING_FRAGMENTS",
 			     "Consecutive strings are generally better as a single string\n" . $herecurr);
 		}