arm/gic-v3: Parse per-cpu redistributor entry in GICC subtable

arm/gic-v3: Parse per-cpu redistributor entry in GICC subtable

The redistributor address can be specified either as part of GICC or
GICR subtable depending on the power domain. The current driver
doesn't support parsing redistributor entry that is defined in GICC
subtable. The GIC CPU subtable entry holds the associated Redistributor
base address if it is not on always-on power domain.

The per CPU Redistributor size is not defined in ACPI specification.
Set the GICR region size to SZ_256K if the GIC hardware is capable of
Direct Virtual LPI Injection feature, SZ_128K otherwise.

This patch adds necessary code to handle both types of Redistributors
base addresses.

Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Acked-by: Julien Grall <julien.grall@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>