drm/msm/mdp5: use 2 memory clients for YUV formats on newer mdp5

Newer MDP5 uses 2 shared memory pool clients for certain YUV formats.
For example, if VIG0 is used to fetch data in YUYV format, it will use
VIG0_Y for Y component, and VIG0_Cr for UV packed.

Signed-off-by: Wentao Xu <wentaox@codeaurora.org>
[rebase]
Signed-off-by: Stephane Viau <sviau@codeaurora.org>