msm: mdss: Add SMP parameters into hw capabilites

To handle use cases better, expose smp_mb_cnt and
smp_mb_per_pipe to userspace as part of hardware capability.
Pipes availablity for a use case can be computed taking these
values, based on which, composition decisions can be made.

Change-Id: Ia7cc4db153cdb164a29ae2369d3e991b95aaba65
Signed-off-by: Mayank Chopra <makchopra@codeaurora.org>