disp: msm: dsi: fix out of bounds access errors

This change fixes the invalid memory access. It allocates
enough memory so that out of bounds access is avoided.

Change-Id: I0749eac54cfa91891a4377b99fbd7f24dd3bd02a
Signed-off-by: Satya Rama Aditya Pinapala <psraditya30@codeaurora.org>