ARM: dts: exynos: Fix regulator name to avoid forbidden character on exynos4210-trats

The usage of slash character causes failure when creating regulator
debugfs entry.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
[k.kozlowski: Write commit message]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

arch/arm/boot/dts/exynos4210-trats.dts

@@ -359,7 +359,7 @@ vcam_reg: LDO7 {
 			};
 
 			vusbdac_reg: LDO8 {
-			     regulator-name = "VUSB/VDAC_3.3V_C210";
+			     regulator-name = "VUSB+VDAC_3.3V_C210";
 			     regulator-min-microvolt = <3300000>;
 			     regulator-max-microvolt = <3300000>;
 			};