staging: crystalhd: fix signed bug

chd_dec_major is unsigned, so check chd_dec_major < 0 doesn't make sense.
Since it is used as signed, declare it as int.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/crystalhd/crystalhd_lnx.h

@@ -76,7 +76,7 @@ struct crystalhd_adp {
 	spinlock_t		lock;
 
 	/* API Related */
-	unsigned int		chd_dec_major;
+	int		chd_dec_major;
 	unsigned int		cfg_users;
 
 	struct crystalhd_ioctl_data	*idata_free_head;	/* ioctl data pool */