KVM: arm64: Don't use __vcpu_sys_reg() to get the address of a sysreg

We are about to prevent the use of __vcpu_sys_reg() as a lvalue,
and getting the address of a rvalue is not a thing.

Update the couple of places where we do this to use the __ctxt_sys_reg()
accessor, which return the address of a register.

Reviewed-by: Miguel Luis <[email protected]>
Reviewed-by: Oliver Upton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Marc Zyngier <[email protected]>

Author: Marc Zyngier

arch/arm64/kvm/arch_timer.c

@@ -1036,7 +1036,7 @@ void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
 	if (vcpu_has_nv(vcpu)) {
 		struct arch_timer_offset *offs = &vcpu_vtimer(vcpu)->offset;
 
-		offs->vcpu_offset = &__vcpu_sys_reg(vcpu, CNTVOFF_EL2);
+		offs->vcpu_offset = __ctxt_sys_reg(&vcpu->arch.ctxt, CNTVOFF_EL2);
 		offs->vm_offset = &vcpu->kvm->arch.timer_data.poffset;
 	}
 

arch/arm64/kvm/fpsimd.c

@@ -103,8 +103,8 @@ void kvm_arch_vcpu_ctxsync_fp(struct kvm_vcpu *vcpu)
 		fp_state.sve_state = vcpu->arch.sve_state;
 		fp_state.sve_vl = vcpu->arch.sve_max_vl;
 		fp_state.sme_state = NULL;
-		fp_state.svcr = &__vcpu_sys_reg(vcpu, SVCR);
-		fp_state.fpmr = &__vcpu_sys_reg(vcpu, FPMR);
+		fp_state.svcr = __ctxt_sys_reg(&vcpu->arch.ctxt, SVCR);
+		fp_state.fpmr = __ctxt_sys_reg(&vcpu->arch.ctxt, FPMR);
 		fp_state.fp_type = &vcpu->arch.fp_type;
 
 		if (vcpu_has_sve(vcpu))