Nobody checks the return codes, so make them return void. Indeed, if the
LLDD cannot send an event, nothing much can be done in the LLDD about it.

Also remove prototype for sas_notify_phy_event() in sas_internal.h, which
should not be there.

Link: https://lore.kernel.org/r/1645786656-221630-2-git-send-email-john.garry@huawei.comReviewed-by: Xiang Chen <chenxiang66@hisilicon.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>