arm64: Repaint ID_AA64MMFR2_EL1.IDS description

ID_AA64MMFR2_EL1.IDS, as described in the sysreg file, is pretty horrible
as it diesctly give the ESR value. Repaint it using the usual NI/IMP
identifiers to describe the absence/presence of FEAT_IDST.

Also add the new EL3 routing feature, even if we really don't care about it.

Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Link: https://patch.msgid.link/20260108173233.2911955-2-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: Marc Zyngier

arch/arm64/kvm/hyp/nvhe/sys_regs.c

@@ -134,7 +134,7 @@ static const struct pvm_ftr_bits pvmid_aa64mmfr2[] = {
 	MAX_FEAT(ID_AA64MMFR2_EL1, UAO, IMP),
 	MAX_FEAT(ID_AA64MMFR2_EL1, IESB, IMP),
 	MAX_FEAT(ID_AA64MMFR2_EL1, AT, IMP),
-	MAX_FEAT_ENUM(ID_AA64MMFR2_EL1, IDS, 0x18),
+	MAX_FEAT(ID_AA64MMFR2_EL1, IDS, IMP),
 	MAX_FEAT(ID_AA64MMFR2_EL1, TTL, IMP),
 	MAX_FEAT(ID_AA64MMFR2_EL1, BBM, 2),
 	MAX_FEAT(ID_AA64MMFR2_EL1, E0PD, IMP),

arch/arm64/tools/sysreg

@@ -2256,9 +2256,10 @@ UnsignedEnum	43:40	FWB
 	0b0000	NI
 	0b0001	IMP
 EndEnum
-Enum	39:36	IDS
-	0b0000	0x0
-	0b0001	0x18
+UnsignedEnum	39:36	IDS
+	0b0000	NI
+	0b0001	IMP
+	0b0010	EL3
 EndEnum
 UnsignedEnum	35:32	AT
 	0b0000	NI