isci: unify constants

cross driver constants are spread out over multiple header files, consolidate
them into isci.h, and push some includes out to the source files that need
them.

TODO: remove SCI_MODE_SIZE infrastructure.
TODO: task.h is full of inlines that are too large

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/scsi/isci/probe_roms.h

@@ -58,6 +58,7 @@
 #ifdef __KERNEL__
 #include <linux/firmware.h>
 #include <linux/pci.h>
+#include "isci.h"
 
 struct isci_orom *isci_request_oprom(struct pci_dev *pdev);