[MIPS] Fix fpu_save_double on 64-bit.
> Without this fix, _save_fp() in 64-bit kernel is seriously broken.
>
>
ffffffff8010bec0 <_save_fp>:
>
ffffffff8010bec0:
400d6000 mfc0 t1,c0_status
>
ffffffff8010bec4:
000c7140 sll t2,t0,0x5
>
ffffffff8010bec8:
05c10011 bgez t2,
ffffffff8010bf10 <_save_fp+0x50>
>
ffffffff8010becc:
00000000 nop
>
ffffffff8010bed0:
f4810328 sdc1 $f1,808(a0)
> ...
Fix register usage in fpu_save_double() and make fpu_restore_double()
more symmetric with fpu_save_double().
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>