MIPS: math-emu: Factor out CFC1/CTC1 emulation

Move CFC1/CTC1 emulation code to separate functions to avoid excessive
indentation in forthcoming changes.  Adjust formatting in a minor way
and remove extraneous round brackets.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9682/


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