isci: unify phy data structures

Make scic_sds_phy a member of isci_phy and merge their lifetimes which
means removing the phy table from scic_sds_controller in favor of the
one at that isci_host level.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>