This reverts commit 
3520f9c779bed098ca76dd3fb6377264301d57ed
("mpt2sas: Remove phys on topology change")
Reverting the previous mpt2sas drives patch changes,
since we will observe below issue
Issue:
Drives connected Enclosure/Expander will unregister with
SCSI Transport Layer, if any one remove and add expander
cable with in DMD (Device Missing Delay) time period or
even any one power-off and power-on the Enclosure with in
the DMD period.
Cc: <stable@vger.kernel.org>
Signed-off-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
 
                    &mpt2sas_phy->remote_identify);
                _transport_add_phy_to_an_existing_port(ioc, sas_node,
                    mpt2sas_phy, mpt2sas_phy->remote_identify.sas_address);
-       } else {
+       } else
                memset(&mpt2sas_phy->remote_identify, 0 , sizeof(struct
                    sas_identify));
-               _transport_del_phy_from_an_existing_port(ioc, sas_node,
-                   mpt2sas_phy);
-       }
 
        if (mpt2sas_phy->phy)
                mpt2sas_phy->phy->negotiated_linkrate =