Bluetooth: SDP: Check tail room of allocated buffer

In partial resolved notification case, there is a case that the tail
room of new allocated buffer is not bigger than the tail room of the
current receiving buffer. Since, the new allocated buffer has the same
size with the current receiving buffer, it means a complete SDP record
cannot fit into the allocated buffer. In this way, the following SDP
discovery should be stopped.

In partial resolved notification case, if the tail room of the new
allocated buffer is not more the tail room of the current receiving
buffer, reports the error `-ENOMEM` and stop the following SDP
discovery.

Signed-off-by: Lyle Zhu <lyle.zhu@nxp.com>