powerpc: Fix up implicit sched.h users

powerpc: Fix up implicit sched.h users

They are getting it through device.h --> module.h path, but we want
to clean that up.  This is a sample of what will happen if we don't:

  pseries/iommu.c: In function 'tce_build_pSeriesLP':
  pseries/iommu.c:136: error: implicit declaration of function 'show_stack'

  pseries/eeh.c: In function 'eeh_token_to_phys':
  pseries/eeh.c:359: error: 'init_mm' undeclared (first use in this function)

  pseries/eeh_event.c: In function 'eeh_event_handler':
  pseries/eeh_event.c:63: error: implicit declaration of function 'daemonize'
  pseries/eeh_event.c:64: error: implicit declaration of function 'set_current_state'
  pseries/eeh_event.c:64: error: 'TASK_INTERRUPTIBLE' undeclared (first use in this function)
  pseries/eeh_event.c:64: error: (Each undeclared identifier is reported only once
  pseries/eeh_event.c:64: error: for each function it appears in.)
  pseries/eeh_event.c: In function 'eeh_thread_launcher':
  pseries/eeh_event.c:109: error: 'CLONE_KERNEL' undeclared (first use in this function)

  hotplug-cpu.c: In function 'pseries_mach_cpu_die':
  hotplug-cpu.c:115: error: implicit declaration of function 'idle_task_exit'

  kernel/swsusp_64.c: In function 'do_after_copyback':
  kernel/swsusp_64.c:17: error: implicit declaration of function 'touch_softlockup_watchdog'

  cell/spufs/context.c: In function 'alloc_spu_context':
  cell/spufs/context.c:60: error: implicit declaration of function 'get_task_mm'
  cell/spufs/context.c:60: warning: assignment makes pointer from integer without a cast
  cell/spufs/context.c: In function 'spu_forget':
  cell/spufs/context.c:127: error: implicit declaration of function 'mmput'

  pasemi/dma_lib.c: In function 'pasemi_dma_stop_chan':
  pasemi/dma_lib.c:332: error: implicit declaration of function 'cond_resched'

  sysdev/fsl_lbc.c: In function 'fsl_lbc_ctrl_irq':
  sysdev/fsl_lbc.c:247: error: 'TASK_NORMAL' undeclared (first use in this function)

Add in sched.h so these get the definitions they are looking for.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>