Rework udf_gro_rename() to be more linear instead of nesting if/else
branching.
vp is used, so don't (void) it
udf_gro_genealogy() : source and destination should never be the same on call,
KASSERT it instead of checking for it.
Switch a few remaining system/pathname configuration variables from
"Dv {xxx}" to "Brq Dv xxx".
Adding _rtadvd to group check.
Add _rtadvd to uid check as well.
And add a skip for the deleted _gpio in uid.
Let init be built easily with the CHROOT capability enabled.

This allows the ramdisk used in the incoming support for full-disk encryption to contain crunched binaries (much like sysinst) while booting a regular system (unlike sysinst).
Build the cgdroot ramdisk by default (for full-disk encryption support). It currently contains the same utilities found in an amd64 sysinst ramdisk, which should be useful in case of emergency.
Common definitions for full-disk encryption support, including the rc script responsible for asking the passphrase and chrooting. wsconsctl is also built and used in case a splash screen is enabled.
Enabled building the kernel module containing the ramdisk required for full-disk encryption support by default. This should be the last part necessary on the amd64 port.

XXX reproduce and test on the i386 port
XXX implement support for full-disk encryption installs in sysinst
note that Makefile.netbsd-gmp can help with the running of configure.
stop abusing kmem during softint context