Fix tracking of hardware state for dump

At end of AudioFlinger::onFirstRef(), the hardware status was being left
in wrong state.  It should be AUDIO_HW_IDLE but was AUDIO_HW_INIT.

mHardwareStatus was being set to AUDIO_HW_OUTPUT_OPEN too early, and so
a return would leave it in the wrong state until next hardware operation.

Take the hardware lock for dev->get_parameters, and update mHardwareStatus
before and after.

Keep hardware lock only for the duration of the dev->set_parameters.

Rename two constants in enum hardware_call_state to have the prefix
AUDIO_HW so they follow the naming conventions.

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Change-Id: I6c7450b11f9b13adaeef9cec874333e478a58fc0