more trivial signedness fixes in drivers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sound/usb/usbaudio.c

@@ -2876,7 +2876,7 @@ static int create_fixed_stream_quirk(struct snd_usb_audio *chip,
 	struct audioformat *fp;
 	struct usb_host_interface *alts;
 	int stream, err;
-	int *rate_table = NULL;
+	unsigned *rate_table = NULL;
 
 	fp = kmemdup(quirk->data, sizeof(*fp), GFP_KERNEL);
 	if (! fp) {