SDP: Include the offset in sdp_disc_server_rsp

The commit
  SDP: Pass the bounds to process_service_*_rsp
with the change ID
  Icf53d4d05f99b5e0a2b3f4d3735b6fbfd62adaa3
omitted the offset when calculating the end of the message.

Bug: 68161546
Test: Connect a headset
Change-Id: I6266b51e3871ed6ce9932161e4ab66de90af4ce6