msm: display: Limit dynamic fps feature only to MIPI video panels.

As dynamic fps feature is supported only for MIPI video panels,
return -EINVAL if sysfs node is written for panels other than
MIPI video. This change also removes world writable permissions
for sysfs node.

Change-Id: I72260e6032cb8a758b0457c36a808263a981260f
Signed-off-by: Vishnuvardhan Prodduturi <vproddut@codeaurora.org>
msm_fb: display: no native frame buffer memory operations

Since we don't use pan_display, the native frame buffer memory is not
necessary any more. This is driver change, mainly disabling memory
operations that are associated with native frame buffers.

CRs-fixed: 458938
Change-Id: If33bff32ee1d9228ff8a74ca09961a0f10f1fcdd
Signed-off-by: Huaibin Yang <huaibiny@codeaurora.org>