arm64: Add encoding for PIRE0_EL2

PIRE0_EL2 is the equivalent of PIRE0_EL1 for the EL2&0 translation
regime, and it is sorely missing from the sysreg file.

Add the sucker.

Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20241023145345.1613824-4-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

Author: Marc Zyngier

arch/arm64/tools/sysreg

@@ -2882,6 +2882,10 @@ Sysreg	PIRE0_EL12	3	5	10	2	2
 Fields	PIRx_ELx
 EndSysreg
 
+Sysreg	PIRE0_EL2	3	4	10	2	2
+Fields	PIRx_ELx
+EndSysreg
+
 Sysreg	PIR_EL1		3	0	10	2	3
 Fields	PIRx_ELx
 EndSysreg