Fix bta_av_do_start handle null p_data

bta_av_do_start may not have p_data for indicating using lateny mode
when resume av stream at call end and second stream needs to start.

Bug: 246442093
Tag: #feature
Ignore-AOSP-First: TM QPR1 feature
Test: test on sink device support dynamic spatial audio
Change-Id: Id22ac500625f184323e3658c3927e66cc806370f