o add CFI_SUPPORT_STRATAFLASH compile option to enable support
o add new ioctls to get/set the factory and user/oem segments of the PR
and to get/set Protection Lock Register that fuses the user segment
o add #defines for bits in the status register
o update cfi_wait_ready to take an offset so it can be used to wait for
PR write completion and replace constants w/ symbolic names
Note: writing the user segment isn't correct; committing now to get review.
Sponsored by: Carlson Wireless
Reviewed by: imp, Chris Anderson