ARM: dts: Add CPU cooling binding for exynos3250 boards

This patch add the cooling device to control the overheating issue on
Exynos3250-based Rinato/Monk board.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>
diff --git a/arch/arm/boot/dts/exynos3250-rinato.dts b/arch/arm/boot/dts/exynos3250-rinato.dts
index ddd7ac2..0e62a64 100644
--- a/arch/arm/boot/dts/exynos3250-rinato.dts
+++ b/arch/arm/boot/dts/exynos3250-rinato.dts
@@ -107,6 +107,21 @@
 		min-microvolt = <1100000>;
 		max-microvolt = <2700000>;
 	};
+
+	thermal-zones {
+		cpu_thermal: cpu-thermal {
+			cooling-maps {
+				map0 {
+					/* Corresponds to 500MHz */
+					cooling-device = <&cpu0 5 5>;
+				};
+				map1 {
+					/* Corresponds to 200MHz */
+					cooling-device = <&cpu0 8 8>;
+				};
+			};
+		};
+	};
 };
 
 &adc {