drm/radeon: Clean up errors in radeon.h

Fix the following errors reported by checkpatch:

ERROR: open brace '{' following struct go on the same line
Signed-off-by: XueBing Chen <chenxb_99091@126.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon.h

@@ -1355,14 +1355,12 @@ struct radeon_dpm_thermal {
 	bool               high_to_low;
 };
 
-enum radeon_clk_action
-{
+enum radeon_clk_action {
 	RADEON_SCLK_UP = 1,
 	RADEON_SCLK_DOWN
 };
 
-struct radeon_blacklist_clocks
-{
+struct radeon_blacklist_clocks {
 	u32 sclk;
 	u32 mclk;
 	enum radeon_clk_action action;