This backport includes revisions 322453, 324339, 324340, 324341, 324363
plus some manual fixes for armv7eb cehcks in Makefiles in gnu.
I booted it on RPi2, boots fine:
root@rpi2-11:~ # uname -a
FreeBSD rpi2-11 11.1-STABLE FreeBSD 11.1-STABLE #0 r332507M: Sat Apr 14 16:14:06 PDT 2018 gonzo@station.bluezbox.com:/src/FreeBSD/obj/arm.armv7/src/FreeBSD/11/sys/RPI2 arm