KVM: arm64: nv: Advertise FEAT_SpecSEI to NV-enabled VMs

FEAT_SpecSEI is an informational feature describing whether speculative
loads may generate SErrors. Since there are already cases where KVM
reinjects an SError into the VM it is already possible this may happen
due to a speculative load within the VM.

Stop hiding the feature from NV-enabled VMs.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: oupton

arch/arm64/kvm/nested.c

@@ -1529,7 +1529,6 @@ u64 limit_nv_id_reg(struct kvm *kvm, u32 reg, u64 val)
 			 ID_AA64MMFR1_EL1_nTLBPA	|
 			 ID_AA64MMFR1_EL1_ETS		|
 			 ID_AA64MMFR1_EL1_XNX		|
-			 ID_AA64MMFR1_EL1_SpecSEI	|
 			 ID_AA64MMFR1_EL1_HAFDBS);
 		/* FEAT_E2H0 implies no VHE */
 		if (test_bit(KVM_ARM_VCPU_HAS_EL2_E2H0, kvm->arch.vcpu_features))