Merge tag 'drm-amdkfd-fixes-2018-04-24' of git://people.freedesktop.org/~gabbayo...

- fix amdkfd Kconfig to select MMU_NOTIFIER
- allow clock retrieval in case GPU not present
- fix return code from function
- make function static (fix sparse warning)

* tag 'drm-amdkfd-fixes-2018-04-24' of git://people.freedesktop.org/~gabbayo/linux:
  drm/amdkfd: fix build, select MMU_NOTIFIER
  drm/amdkfd: fix clock counter retrieval for node without GPU
  drm/amdkfd: Fix the error return code in kfd_ioctl_unmap_memory_from_gpu()
  drm/amdkfd: kfd_dev_is_large_bar() can be static