checkpatch: fix USLEEP_RANGE test

Do not test udelay() for a value less than 10usec when passed a variable
instead of a hard-coded number; there is no way for checkpatch to know the
value of the variable.  As it is today, it will complain about variables
with alphanumeric characters plus '_', e.g.  foo_bar, but not variables
with other characters, eg.  foo->bar.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 7b40a3f..747bcd7 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3253,9 +3253,9 @@
 		}
 
 # prefer usleep_range over udelay
-		if ($line =~ /\budelay\s*\(\s*(\w+)\s*\)/) {
+		if ($line =~ /\budelay\s*\(\s*(\d+)\s*\)/) {
 			# ignore udelay's < 10, however
-			if (! (($1 =~ /(\d+)/) && ($1 < 10)) ) {
+			if (! ($1 < 10) ) {
 				CHK("USLEEP_RANGE",
 				    "usleep_range is preferred over udelay; see Documentation/timers/timers-howto.txt\n" . $line);
 			}