scsi: libsas: Co-locate exports with symbols

It is standard practice to co-locate export declarations with the symbol
which is being exported. Or at least in the same file - see
sas_phy_reset().

Modify libsas to follow this practice consistently.

Link: https://lore.kernel.org/r/1631530296-32358-1-git-send-email-john.garry@huawei.com


Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>