use the MetadataBufferType defined in frameworks/native

Change-Id: Ifb56622b7d0464e683882ef5b7c89e6dc5c8a097
Signed-off-by: Lajos Molnar <lajos@google.com>
camera bringup changes hardware-qcom-media

Change-Id: I4b81d2150e5bbd97d09c91f3cf89a8c6169b6058