st-hal: Prevent multiple consecutive device enablements

In capture concurrency usecases, the device disable can be skipped
due to audio hal continuing to need the device. In these usecases,
do not allow sthal to enable the same device again as it throws off
the mixer control reference count.

Change-Id: I8f905901f705f7c6c38b27ed547f2d609efcdf4c
5 files changed