C2 VTS: use mime instead of component name in DecodeTest

Following CL merged a commit from android10-tests-dev to
android12-tests-dev

https://android-review.googlesource.com/c/platform/frameworks/av/+/1851097

and this resulted in build failure as DecodeTest now doesn't
use component name for codec specific checks.
This is now fixed by checking mime instead of component name
for g711 checks.

Bug: 202600369
Test: atest VtsHalMediaC2V1_0TargetAudioDecTest

Change-Id: I88d60e0ea198c6f2c48899753f501e44961a090a