ArmPkg: Add support for GICv4

ArmPkg: Add support for GICv4

Updated Redistributor base calculation to allow for the fact that
GICv4 has 2 additional 64KB frames (for VLPI and a reserved frame).
The code now tests the VLPIS bit in the GIC Redistributor Type
Register (GICR_TYPER) and calculates the Redistributor granularity
accordingly.

The code changes are:
  GICR_TYPER register fields, etc, added to the header.
  Loop updated to pay attention to GICR_TYPER.Last.
  Derive frame "stride" size from GICR_TYPER.VLPIS.

Note: The assumption is that the redistributors are adjacent for
all CPUs. However this may not be the case for NUMA systems.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>