uwb: don't unbind the radio controller driver when resetting

Use pre_reset and post_reset methods to avoid unbinding the radio
controller driver after a uwb_rc_reset_all() call.  This avoids a
deadlock in uwb_rc_rm() when waiting for the uwb event thread to stop.

Signed-off-by: David Vrabel <david.vrabel@csr.com>

include/linux/uwb/umc.h

@@ -89,6 +89,8 @@ struct umc_driver {
 	void (*remove)(struct umc_dev *);
 	int  (*suspend)(struct umc_dev *, pm_message_t state);
 	int  (*resume)(struct umc_dev *);
+	int  (*pre_reset)(struct umc_dev *);
+	int  (*post_reset)(struct umc_dev *);
 
 	struct device_driver driver;
 };