Renamed _transport_add_phy_to_an_existing_port() to
mpt3sas_transport_add_phy_to_an_existing_port() and
_transport_del_phy_from_an_existing_port() to
mpt3sas_transport_del_phy_from_an_existing_port() as the driver needs to
call these functions from outside mpt3sas_transport.c file.

Added extra function argument 'port' of type struct hba_port to above
functions and check for portID before adding/removing the phy from the
_sas_port object.  I.e. add/remove the phy from _sas_port object only if
_sas_port's port object and phy's port object are the same.

Link: https://lore.kernel.org/r/20201027130847.9962-7-sreekanth.reddy@broadcom.comSigned-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>