The arm, mips, and riscv MD Symbol.map files listed some (but not all)
of the softfloat symbols that were actually defined in softfloat.c.
While here, also remove entries for __fixuns[sd]fsi which are provided
by libcompiler_rt and not by libc.
Sponsored by: DARPA / AFRL
Hardfloat is now default (use riscv64sf as TARGET_ARCH
for softfloat).
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D8529
They are not used anywhere else in the base system and are an internal
implementation detail that does not need to be exposed.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5728
