vmci/vsock: check SO_RCVLOWAT before wake up reader

This adds extra condition to wake up data reader: do it only when number
of readable bytes >= SO_RCVLOWAT. Otherwise, there is no sense to kick
user, because it will wait until SO_RCVLOWAT bytes will be dequeued. This
check is performed in vsock_data_ready().

Signed-off-by: Arseniy Krasnov <[e-mail]>
Reviewed-by: Vishnu Dasa <[e-mail]>
Signed-off-by: Paolo Abeni <[e-mail]>

net/vmw_vsock/vmci_transport_notify.c

···
 	struct vsock_sock *vsk = vsock_sk(sk);
 	PKT_FIELD(vsk, sent_waiting_read) = false;
 #endif
-	sk->sk_data_ready(sk);
+	vsock_data_ready(sk);
 }
 
 static void vmci_transport_notify_pkt_socket_init(struct sock *sk)

net/vmw_vsock/vmci_transport_notify_qstate.c

···
 			    bool bottom_half,
 			    struct sockaddr_vm *dst, struct sockaddr_vm *src)
 {
-	sk->sk_data_ready(sk);
+	vsock_data_ready(sk);
 }
 
 static void vsock_block_update_write_window(struct sock *sk)
···
 		/* See the comment in
 		 * vmci_transport_notify_pkt_send_post_enqueue().
 		 */
-		sk->sk_data_ready(sk);
+		vsock_data_ready(sk);
 	}
 
 	return err;