VTS: Fix DecodeTest For Audio Decoders.

Removed extra start() from DecodeTest for audio decoders.

Test: VtsHidlC2V1_0TargetAudioDecTest -I software -C c2.android.aac.decoder -P /sdcard/res/

Bug: 127691660

Change-Id: Iff7ecdaad83ea3753c3cd444511f41deee57f782
1 file changed