Unable to build 12.0-STABLE release

[David Boyd]

While attempting to build 12.0-STABLE release images, the following
error message sequence occurs:

make[2]: don't know how to make CHECKSUM.SHA512-FreeBSD-12.0-STABLE-
amd64.asc. Stop.

make[2]: stopped in /usr/doc/en_US.ISO8859-1/htdocs/releases/12.0R
*** Error code 2

Stop.
make[1]: stopped in /usr/src/release
*** Error code 1

Stop.
make: stopped in /usr/src/release

The build of 12.0-RELEASE release images was successful.

The only change made to release.conf.sample was
CHROOTDIR="/u/1/scratch".

The host is 12.0-RELEASE-p1.

I don't have a log of the build, but will acquire one if that would be
useful.

Thanks.

David.