msm: mdss: Add support to change the dma timeout value

Add support to adjust the dma timeout value depending
on the current vsync period. When the panel goes into
idle state, the vsync period will change and hence the
timeout value should be dependent on this value instead
of a constant value.

Change-Id: Ib6d311997f3a23f998d4d02f741ee64a3abee446
Signed-off-by: Krishna Manikandan <mkrishn@codeaurora.org>