Bluetooth: Replace spin_lock by mutex in hci_dev

Now we run everything in HCI in process context, so it's a better idea use
mutex instead spin_lock. The macro remains hci_dev_lock() (and I got rid
of hci_dev_lock_bh()), of course.

Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 3c2d888..d478be1 100644
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -795,11 +795,11 @@
 	if (!hdev)
 		return NULL;
 
-	hci_dev_lock_bh(hdev);
+	hci_dev_lock(hdev);
 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
 	if (conn)
 		hci_conn_hold_device(conn);
-	hci_dev_unlock_bh(hdev);
+	hci_dev_unlock(hdev);
 
 	hci_dev_put(hdev);