For virt, freed mailbox irq should be handled in hw fini, not hw
init. Correct it.
Signed-off-by: NXiangliang Yu <Xiangliang.Yu@amd.com>
Reviewed-by: NMonk Liu <Monk.Liu@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>