[POWERPC] Fix build failure on Cell when CONFIG_SPU_FS=y

Commit aed3a8c9bb1a8623a618232087c5ff62718e3b9a introduced a
definition of notify_spus_active in .../cell/spu_syscalls.c, and
another definition under #ifndef MODULE in .../cell/spufs/sched.c.
The latter is not necessary and causes the build to fail when
CONFIG_SPU_FS=y, so this removes it. It also removes the export
of do_notify_spus_active, which is unnecessary.

Signed-off-by: Paul Mackerras <[e-mail]>
Acked-by: Arnd Bergmann <[e-mail]>
Acked-by: Jeremy Kerr <[e-mail]>

arch/powerpc/platforms/cell/spufs/sched.c

···
 		mutex_unlock(&cbe_spu_info[node].list_mutex);
 	}
 }
-EXPORT_SYMBOL_GPL(do_notify_spus_active);
-
-#ifndef MODULE
-void notify_spus_active(void)
-{
-	do_notify_spus_active();
-}
-EXPORT_SYMBOL_GPL(notify_spus_active);
-#endif
 
 /**
  * spu_bind_context - bind spu context to physical spu