Bluetooth: Use GFP_KERNEL in user context

The allocation in mgmt_control() code are in user context and not locked
by any spinlock, so it's not recommended the use of GFP_ATOMIC there.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

net/bluetooth/mgmt.c

@@ -1581,7 +1581,7 @@ int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
 	if (msglen < sizeof(*hdr))
 		return -EINVAL;
 
-	buf = kmalloc(msglen, GFP_ATOMIC);
+	buf = kmalloc(msglen, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;