USB: make usb_iso_packet_descriptor.status signed

The status in usb_iso_packet_descriptor should be signed, for the benefit
of someone who casts to a long or makes other benign misstep (the principle
of least surprise).
Signed-off-by: NPete Zaitcev <zaitcev@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

include/linux/usb.h

@@ -935,7 +935,7 @@ struct usb_iso_packet_descriptor {
 	unsigned int offset;
 	unsigned int length;		/* expected length */
 	unsigned int actual_length;
-	unsigned int status;
+	int status;
 };
 
 struct urb;