ARM: dts: msm: define max supported memory bandwidth for display

As display resolutions increase, the memory bandwidth requirement
increases as the number of layers supported increase. With these high
memory requirements it's not possible to sustain high memory bandwidth
requirement past a certain threshold without potentially underflowing.
These bandwidth thresholds are different across targets, define these
according to system level profiling results.

Change-Id: I132aeb5f6d83a56c6de8280a3a3a26710477b5fa
Signed-off-by: Sree Sesha Aravind Vadrevu <svadrevu@codeaurora.org>
Signed-off-by: Adrian Salido-Moreno <adrianm@codeaurora.org>