MIPS64: Convert rest of files to use fr1 mode properly.

This is just converting a few mtc1/mfc1 on odd FP regs to use mthc1/mfhc1.

This is a hard-conversion to FR1 mode. To later combine this port with
mips32 will require macro-wrapping these to support either mode. At that
time we will also have to support mips32r1 cpus which do not have these
instructions.