Prepare SDP for convergence

Move sdp test to its own folder and adding them to mts_default for
coverage tracking
Add basic test for service_search_request

Bug: 246022810
Test: atest net_test_stack_sdp
Tag: #refactor
Merged-In: Ic9c80556883e9a84a93bf3757f8b7bb0d8ea0748
Change-Id: Ic9c80556883e9a84a93bf3757f8b7bb0d8ea0748
(cherry picked from commit 26183984)