<sys/param.h> is a superset of <sys/types.h> and must always come
first.  Coincidentally, today is the 11th anniversary of this man
page's (and this bug's) first appearance in FreeBSD.

MFC after:	3 days
Don't zero the stats before they are read out.

MFC after: 3 days
Fix the build of non-FDT systems by moving the gpiobusvar.h header outside
the FDT #ifdef.

While here remove a few unused headers.
Move the definitions of the fdt functions from a uboot header to a new fdt
header. There is nothing in the fdt spec that ties it to U-Boot.

While here sort and fix the signature of fdt_setup_fdtp.

MFC after:	1 week
Merge remote-tracking branch 'freebsd/master' into hardened/current/master
Merge remote-tracking branch 'origin/hardened/current/master' into hardened/current/segvguard