MK_CTF, MK_SSP, MK_PROFILE, NO_PIC, and INTERNALLIB are always the
same, so set them in defs.mk. MAN= is common, so set it here too.
This removes a lot of boring repetition from the Makefiles that added
almost no value.
Remove the now-useless dependency on ufsread.c. In some cases, it was
on the wrong file. But in all cases, we now automatically generate
.depend files, so we don't need it explicitly.
Sponsored by: Netflix
