Make libaudiofoundation can be a static library.

As libaudiofoundation is not part of VNDK, it may break VTS build. Make
libaudiofoundation be a static library can help solve the problem.

Test: make, atest VtsHalAudioV5_0Target
Bug: 142683018
Change-Id: I814c5380dfa5269fccc7bd37e29f308f1bc9bf28
1 file changed