KVM: arm64: Don't advertises GICv3 in ID_PFR1_EL1 if AArch32 isn't supported

Although the AArch32 ID regs are architecturally UNKNOWN when AArch32
isn't supported at any EL, KVM makes a point in making them RAZ.

Therefore, advertising GICv3 in ID_PFR1_EL1 must be gated on AArch32
being supported at least at EL0.

Fixes: a258a383b9177 ("KVM: arm64: gic-v5: Sanitize ID_AA64PFR2_EL1.GCIE")
Reported-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Message-ID: <20260326153530.3981879-16-maz@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>