Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

choose the size of the last region for d_stripsize instead of the first;
this fixes geom_redboot on boards that have multiple parts/regions as it
uses the value to locate the FIS directory which is in the last erase
region of flash

Add cfid, a disk interface to CFI flash devices; this enables construction
of flash-based filesystems.

Note this is not interlocked against the raw CFI device.