Revert "msm: vidc: Overwrite max mbs per frame value in driver"

This reverts commit 87763ddc ("msm: vidc: Overwrite max mbs per
frame value in driver")

This issue has been fixed in Venus fw.

Change-Id: If17366ac6cb7bd4d8e172df7f784b68db5391139
Signed-off-by: Vikash Garodia <vgarodia@codeaurora.org>