isci: refactor initialization for S3/S4

isci: refactor initialization for S3/S4

Based on an original implementation by Ed Nadolski and Artur Wojcik

In preparation for S3/S4 support refactor initialization so that
driver-load and resume-from-suspend can share the common init path of
isci_host_init().  Organize the initialization into objects that are
self-contained to the driver (initialized by isci_host_init) versus
those that have some upward registration (initialized at allocation time
asd_sas_phy, asd_sas_port, dma allocations).  The largest change is
moving the the validation of the oem and module parameters from
isci_host_init() to isci_host_alloc().

The S3/S4 approach being taken is that libsas will be tasked with
remembering the state of the domain and the lldd is free to be
forgetful.  In the case of isci we'll just re-init using a subset of the
normal driver load path.

[clean up some unused / mis-indented function definitions in host.h]

Signed-off-by: Ed Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>