qdutils : Read max mixer width from drivers.

Read the maximum width mixer can output from drivers
and consider this in identifying if dual pipes are required
to support a layer. So far above 2K dimensions we are using dual
pipes, but 8x39 mixer output can be upto 2560. So there is no
need of dual pipes as long as pipe data is less than this limit.
Compare layer/panel resolutions against this limit to deduce
if there is a need for dual pipes or split.

Change-Id: I52e1d28e381327d4f0b00f5ea8547c1e6157313c