The contents of these files was copied from defs.h and findvar. Copy
over the copyright years (1986-2024).
Change-Id: Idfb0f255fbcfda7e107e9a82804cece3d81ed5fc
Move the declarations out of defs.h, and the implementations out of
findvar.c.
I opted for a new file, because this functionality of converting
integers to bytes and vice-versa seems a bit to generic to live in
findvar.c.
Change-Id: I524858fca33901ee2150c582bac16042148d2251
Approved-By: John Baldwin <jhb@FreeBSD.org>