r261567: Build a 32-bit libstand under sys/boot/
A 32-bit libstand is needed on 64-bit platforms for use by various bootloaders. Previously only the 32-bit version was built, installed as /usr/lib/libstand.a. A new 64-bit libstand consumer will arrive in the near future, so move the bootloader-specific 32-bit version to sys/boot/libstand32/. Explicitly link against this version in the 32-bit loaders.
r261614: Build a 32-bit libstand under sys/boot/ for ppc64
This change is equivalent to r261567 for i386/amd64.
Relnotes: Yes
Sponsored by: The FreeBSD Foundation