Merge branch 'drm-fixes-4.12' of git://people.freedesktop.org/~agd5f/linux into drm-fixes

A bunch of bug fixes:
- Fix display flickering on some chips at high refresh rates
- suspend/resume fix
- hotplug fix
- a couple of segfault fixes for certain cases

* 'drm-fixes-4.12' of git://people.freedesktop.org/~agd5f/linux:
  drm/amdgpu: fix null point error when rmmod amdgpu.
  drm/amd/powerplay: fix a signedness bugs
  drm/amdgpu: fix NULL pointer panic of emit_gds_switch
  drm/radeon: Unbreak HPD handling for r600+
  drm/amd/powerplay/smu7: disable mclk switching for high refresh rates
  drm/amd/powerplay/smu7: add vblank check for mclk switching (v2)
  drm/radeon/ci: disable mclk switching for high refresh rates (v2)
  drm/amdgpu/ci: disable mclk switching for high refresh rates (v2)
  drm/amdgpu: fix fundamental suspend/resume issue