msm: mdss: Move bus scale table implementation to device-tree

Bus scale table is chip-set dependent where number of paths per
bandwidth use-case can differ chip-set to chip-set. Current
implementation has a static table where it supports only one path per
use-case. Expand MDSS bus scaling implementation to accommodate
chip-sets where more than one path per use-case, i.e. apq8084, is
possible and move table initialization to device-tree so that every
chip-set configures its own table.

Change-Id: Ia6f76654d129fe0ec1a7124aa87b16f96167fe84
Signed-off-by: Ujwal Patel <ujwalp@codeaurora.org>