ARMv8/ls2085a_emu: Add LS2085A emulator and simulator board support

LS2085A is an ARMv8 implementation. This adds board support for emulator
and simulator:
  Two DDR controllers
  UART2 is used as the console
  IFC timing is tightened for speedy booting
  Support DDR3 and DDR4 as separated targets
  Management Complex (MC) is enabled
  Support for GIC 500 (based on GICv3 arch)

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Arnab Basu <arnab.basu@freescale.com>
Signed-off-by: J. German Rivera <German.Rivera@freescale.com>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@freescale.com>