drm/etnaviv: Simplify clock enable/disable

All the NULL checks are pointless, clk_*() routines already deal with NULL
just fine.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>

drivers/gpu/drm/etnaviv/etnaviv_gpu.c

@@ -1487,40 +1487,29 @@ static int etnaviv_gpu_clk_enable(struct etnaviv_gpu *gpu)
 {
 	int ret;
 
-	if (gpu->clk_reg) {
 	ret = clk_prepare_enable(gpu->clk_reg);
 	if (ret)
 		return ret;
-	}
 
-	if (gpu->clk_bus) {
 	ret = clk_prepare_enable(gpu->clk_bus);
 	if (ret)
 		goto disable_clk_reg;
-	}
 
-	if (gpu->clk_core) {
 	ret = clk_prepare_enable(gpu->clk_core);
 	if (ret)
 		goto disable_clk_bus;
-	}
 
-	if (gpu->clk_shader) {
 	ret = clk_prepare_enable(gpu->clk_shader);
 	if (ret)
 		goto disable_clk_core;
-	}
 
 	return 0;
 
 disable_clk_core:
-	if (gpu->clk_core)
 	clk_disable_unprepare(gpu->clk_core);
 disable_clk_bus:
-	if (gpu->clk_bus)
 	clk_disable_unprepare(gpu->clk_bus);
 disable_clk_reg:
-	if (gpu->clk_reg)
 	clk_disable_unprepare(gpu->clk_reg);
 
 	return ret;
@@ -1528,13 +1517,9 @@ static int etnaviv_gpu_clk_enable(struct etnaviv_gpu *gpu)
 
 static int etnaviv_gpu_clk_disable(struct etnaviv_gpu *gpu)
 {
-	if (gpu->clk_shader)
 	clk_disable_unprepare(gpu->clk_shader);
-	if (gpu->clk_core)
 	clk_disable_unprepare(gpu->clk_core);
-	if (gpu->clk_bus)
 	clk_disable_unprepare(gpu->clk_bus);
-	if (gpu->clk_reg)
 	clk_disable_unprepare(gpu->clk_reg);
 
 	return 0;