Add ARMv8.2 ID_AA64MMFR0_EL1.PARange value

If an implementation of ARMv8.2 includes ARMv8.2-LPA, the value 0b0110
is permitted in ID_AA64MMFR0_EL1.PARange, which means that the Physical
Address range supported is 52 bits (4 PiB). It is a reserved value
otherwise.

Change-Id: Ie0147218e9650aa09f0034a9ee03c1cca8db908a
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>