Add missing functions and signatures for older OMX video libs compat

Nvidia OMX libs need these to work
That fixes hardware OMX video codecs + Camera on TF101

AudioTrack: Do not inline getSessionId either

Should help for other nvomx versions that requires it.

to use, set the following flag in your BoardConfig:
TARGET_USE_OMAP_COMPAT := true

Change-Id: I9f9afa844edf3e6d1fd25524f2cc155b974245ec