isci: add support for 2 more oem parmeters

isci: add support for 2 more oem parmeters

1/ add OEM paramater support for mode_type (MPC vs APC)
2/ add OEM parameter support for max_number_concurrent_device_spin_up
3/ cleanup scic_sds_controller_start_next_phy

todo: hook up the amp control afe parameters into the afe init code

Signed-off-by: Henryk Dembkowski <henryk.dembkowski@intel.com>
Signed-off-by: Jacek Danecki <Jacek.Danecki@intel.com>
[cleaned up scic_sds_controller_start_next_phy]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>