KVM: arm64: vgic: Add a non-locking primitive for kvm_vgic_vcpu_destroy()

KVM: arm64: vgic: Add a non-locking primitive for kvm_vgic_vcpu_destroy()

commit d26b9cb33c2d1ba68d1f26bb06c40300f16a3799 upstream.

As we are going to need to call into kvm_vgic_vcpu_destroy() without
prior holding of the slots_lock, introduce __kvm_vgic_vcpu_destroy()
as a non-locking primitive of kvm_vgic_vcpu_destroy().

Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231207151201.3028710-3-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>