Revert "libstagefright: Fix incorrectness nPortIndex value for QueryCodec"

This reverts commit 9a814ad626233ff02dd2d393929f32225bc94b68.
This is wrong. kPortIndexInput is defined as 0, the original value was correct.
Additionally, it breaks android.media.cts.MediaCodecListTest

Change-Id: Ib273cde69a4c622daf239bab5d12c5e7d568af2f