Bluetooth: AMP: Use set_bit / test_bit for amp_mgr state

Using bit operations solves problems with multiple requests
and clearing state.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
diff --git a/include/net/bluetooth/a2mp.h b/include/net/bluetooth/a2mp.h
index 8b39327..487b54c 100644
--- a/include/net/bluetooth/a2mp.h
+++ b/include/net/bluetooth/a2mp.h
@@ -34,7 +34,7 @@
 	struct kref		kref;
 	__u8			ident;
 	__u8			handle;
-	enum amp_mgr_state	state;
+	unsigned long		state;
 	unsigned long		flags;
 
 	struct list_head	amp_ctrls;