[PORT FROM R42B-STABLE] libmix: Avoid returning unnecessary "format change" error code

BZ: 127926

If video format is not really changed, don't return "DECODE_FORMAT_CHANGE"
error code to caller.

Change-Id: Ib88f5d1f66a704d472bec54ad9e78143cb0fbea5
Signed-off-by: Suneel Kandru <suneel.kandru@intel.com>
4 files changed