hal: Address missing sysfs update during DP disconnect

During display port disconnect, adev_set_parameter() is calling
platform_invalidate_hdmi_config() before the audio extension.
Attempts to read the current display type in order to determine
which sysfs node to communicate with. The solution is to
relocate invalidate function in audio extension to ensure that
it does not get called prematurely.

Change-Id: Ifc7bc8cc753855edacb8fa90a9f784086fef7594
CRs-Fixed: 1082254