powerpc/e500: Save SPEFCSR in flush_spe_to_thread()

giveup_spe() saves the SPE state which is protected by MSR[SPE].
However, modifying SPEFSCR does not trap when MSR[SPE]=0.
And since SPEFSCR is already saved/restored in _switch(),
not all the callers want to save SPEFSCR again.
Thus, saving SPEFSCR should not belong to giveup_spe().

This patch moves SPEFSCR saving to flush_spe_to_thread(),
and cleans up the caller that needs to save SPEFSCR accordingly.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 91e52df..60ac2a9 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -213,6 +213,7 @@
 #ifdef CONFIG_SMP
 			BUG_ON(tsk != current);
 #endif
+			tsk->thread.spefscr = mfspr(SPRN_SPEFSCR);
 			giveup_spe(tsk);
 		}
 		preempt_enable();