audio VTS: Update 7.0/PolicyConfig

The call to instantiate PolicyConfig was updated
in Iced9d665d018853c4b2a50f4471a545af7bf60bb, however
the version of PolicyConfig class for HIDL HAL 7.x
was not updated accordingly

Bug: 205884982
Bug: 281450557
Test: atest VtsHalAudioV7_0TargetTest
Test: atest HalAudioV7_0GeneratorTest
Change-Id: Ic7ed6b186e1d0f1ff853f84ad962c1e4acf17a68