Define KVM_GUESTDBG_VALID_MASK and use it to implement this capabiity.
Compile tested only.
Signed-off-by: NMaxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20210401135451.1004564-6-mlevitsk@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>