drm/radeon: add DCE8 macro for CIK

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index f5fccbb..b50a786 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -1841,6 +1841,7 @@
 			     (rdev->flags & RADEON_IS_IGP))
 #define ASIC_IS_DCE64(rdev) ((rdev->family == CHIP_OLAND))
 #define ASIC_IS_NODCE(rdev) ((rdev->family == CHIP_HAINAN))
+#define ASIC_IS_DCE8(rdev) ((rdev->family >= CHIP_BONAIRE))
 
 /*
  * BIOS helpers.