msm: camera: Define meta data stream marker bit

Bit 19 (0x80000) is defined as the marker of meta data stream.
In current implementation, kernel stream ID marker bits are all
defined in kernel header file.
Define kernel stream marker bit here reserves the possibility for
kernel driver to distinguish different types of streams.

Change-Id: I5cda2ac80f53fe56a2e08b784d18cd1f53ae9756
Signed-off-by: Mingcheng Zhu <mingchen@codeaurora.org>