Add three items to 12.0-RELEASE errata:
- disc1.iso for amd64 and i386 does not fit onto a 700MB CD.
- boot messages do not list CPUs other than CPU0.
- graphics/drm-kmod should be used instead of graphics/drm-stable-kmod or graphics/drm-legacy-kmod when the 2019Q1 branch is created.
Sponsored by: The FreeBSD Foundation