Update OMX messages for 64 bit

Change node_id and buffer_id to uint32_t.
Ensure IOMX messages are fixed size.
Remove 64 bit compile warnings in associated files.

Change-Id: Icdbef00aca575e5dc502ebb52e3ce7d0d7883203
Signed-off-by: Andy Hung <hunga@google.com>
11 files changed