floppy: fix lock imbalance

A crappy macro prevents us unlocking on a fail path.

Expand the macro and unlock appropriatelly.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/block/floppy.c

@@ -3327,7 +3327,10 @@ static inline int set_geometry(unsigned int cmd, struct floppy_struct *g,
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;
 		mutex_lock(&open_lock);
-		LOCK_FDC(drive, 1);
+		if (lock_fdc(drive, 1)) {
+			mutex_unlock(&open_lock);
+			return -EINTR;
+		}
 		floppy_type[type] = *g;
 		floppy_type[type].name = "user format";
 		for (cnt = type << 2; cnt < (type << 2) + 4; cnt++)