Thermal: exynos: Add clk_{un}prepare APIs

clk_{un}prepare APIs are required to migrate to common
clock framework. While at it convert to use devm_clk_get as
it removes some cleanup code.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Amit Daniel Kachhap <amit.daniel@samsung.com>
Acked-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

drivers/thermal/exynos_thermal.c

@@ -985,12 +985,16 @@ static int exynos_tmu_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	data->clk = clk_get(NULL, "tmu_apbif");
+	data->clk = devm_clk_get(&pdev->dev, "tmu_apbif");
 	if (IS_ERR(data->clk)) {
 		dev_err(&pdev->dev, "Failed to get clock\n");
 		return  PTR_ERR(data->clk);
 	}
 
+	ret = clk_prepare(data->clk);
+	if (ret)
+		return ret;
+
 	if (pdata->type == SOC_ARCH_EXYNOS ||
 				pdata->type == SOC_ARCH_EXYNOS4210)
 		data->soc = pdata->type;
@@ -1046,7 +1050,7 @@ static int exynos_tmu_probe(struct platform_device *pdev)
 	return 0;
 err_clk:
 	platform_set_drvdata(pdev, NULL);
-	clk_put(data->clk);
+	clk_unprepare(data->clk);
 	return ret;
 }
 
@@ -1060,7 +1064,7 @@ static int exynos_tmu_remove(struct platform_device *pdev)
 
 	exynos_unregister_thermal();
 
-	clk_put(data->clk);
+	clk_unprepare(data->clk);
 
 	platform_set_drvdata(pdev, NULL);