ALSA: snd-usb: handle the bmFormats field as unsigned int

This field may use up to 32 bits, so it should be handled as unsigned
int.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Reported-by: Andreas Koch <andreas@akdesigninc.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/stream.c b/sound/usb/stream.c
index ad181d5..ad07046 100644
--- a/sound/usb/stream.c
+++ b/sound/usb/stream.c
@@ -463,7 +463,7 @@
 	struct usb_host_interface *alts;
 	struct usb_interface_descriptor *altsd;
 	int i, altno, err, stream;
-	int format = 0, num_channels = 0;
+	unsigned int format = 0, num_channels = 0;
 	struct audioformat *fp = NULL;
 	int num, protocol, clock = 0;
 	struct uac_format_type_i_continuous_descriptor *fmt;