[MIPS] Unify mips_fpu_soft_struct and mips_fpu_hard_structs.

The struct mips_fpu_soft_struct and mips_fpu_hard_struct are
completely same now and the kernel fpu emulator assumes that.  This
patch unifies them to mips_fpu_struct and get rid of mips_fpu_union.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/branch.c b/arch/mips/kernel/branch.c
index b6232d9..76fd3f2 100644
--- a/arch/mips/kernel/branch.c
+++ b/arch/mips/kernel/branch.c
@@ -178,7 +178,7 @@
 		if (is_fpu_owner())
 			asm volatile("cfc1\t%0,$31" : "=r" (fcr31));
 		else
-			fcr31 = current->thread.fpu.hard.fcr31;
+			fcr31 = current->thread.fpu.fcr31;
 		preempt_enable();
 
 		bit = (insn.i_format.rt >> 2);