Kill sys/cdefs.h includes, because overly complicated include+macro
for a sccsid replacement scheme which results an namespace damage
is an unfair trade
ok bluhm

remove a couple hundred sys/param.h includes in userland code, and
also whack some sys/cdefs.h early includes which is such a brutally
bad pattern
ok bluhm mbuhl

add missing FreeBSD libm tests, update the others