MIPS: math-emu: Remove most ifdefery.

Most of these tests should be runtime tests.  This also finally means
that on a MIPS III systems MIPS IV opcodes are going to result in an
exception as they're supposed to.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --cc arch/mips/include/asm/cpu-features.h
Simple merge

diff --cc arch/mips/math-emu/cp1emu.c
Simple merge

diff --cc arch/mips/math-emu/ieee754.c
Simple merge