Subject: spufs: initialize context correctly

the mfc member of a new context was not initialized to zero,
which potentially leads to wild memory accesses.

From: Dirk Herrendoerfer <herrendo@de.ibm.com>
Signed-off-by: Arnd Bergmann <abergmann@de.ibm.com>

Index: linus-2.6/arch/powerpc/platforms/cell/spufs/context.c
===================================================================
--- linus-2.6.orig/arch/powerpc/platforms/cell/spufs/context.c
+++ linus-2.6/arch/powerpc/platforms/cell/spufs/context.c
@@ -51,6 +51,7 @@ struct spu_context *alloc_spu_context(vo
 	ctx->ibox_fasync = NULL;
 	ctx->wbox_fasync = NULL;
 	ctx->mfc_fasync = NULL;
+	ctx->mfc = NULL;
 	ctx->tagwait = 0;
 	ctx->state = SPU_STATE_SAVED;
 	ctx->local_store = NULL;