[SCSI] mpt2sas: Removed wrapper funtions _scsih_link_change.

Deleted the wrapper function called _scsih_link_change. This function was
implemented for compatibility reasons only, between different kernel versions.
Currently this function is no longer needed.  The calling function are
converted to calling mpt2sas_transport_update_phy_link_change directly in the
transport layer.

Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Reviewed-by: Eric Moore <Eric.moore@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>