msm: mdss: request ab/ib quota based on rt and nrt client

Non-RealTime(NRT) memory fetch should use NRT AXI
ports while RT usecase memory fetch should go through
RT AXI ports. Number of RT and NRT AXI ports can be
different from chipset to chipset. MDSS driver hardcodes
them to "2" for all usecases which won't apply for
all MDP cores Ex: MDPv17. This change removes AXI ports
hard coding and updates ab/ib request based on AXI
ports availability for respective chipset. It uses
uniform calculation method for ib/ab quota request on
RT and NRT AXI ports to reduce the driver complexity
and clean interface.

Change-Id: I015c5c8a64bdf62f5747fcbcf19ba00cd29e21b5
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>