msm: mdss: Fix for bus bandwidth issue

Fixing possible large values handling.

Change-Id: Id9e4aafa2a922c2c90def037b110826344487fcd
Signed-off-by: Radhika Ranjan Soni <rrsoni@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>