Merge branch 'pm-devfreq'

* pm-devfreq:
  PM / devfreq: create_freezable_workqueue() doesn't return an ERR_PTR
  PM / devfreq: Remove duplicate header file inclusion in exynos5_bus.c
  PM / devfreq: Use devm_* APIs in exynos5_bus.c
  PM / devfreq: Remove redundant platform_set_drvdata() in exynos5_bus.c
  PM / devfreq: Fix incorrect usage of IS_ERR_OR_NULL in exynos5_bus.c