dt-bindings: Correct the example for Exynos power domain clocks

Since commit 29e5eea0 ("ARM: EXYNOS: Get current parent clock for
power domain on/off") the "pclkN" names of "clock-names" property is not
parsed any more. The bindings and driver were updated but the example
was not. Fix the example now.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>

Documentation/devicetree/bindings/arm/exynos/power_domain.txt

@@ -43,9 +43,8 @@ Example:
 	mfc_pd: power-domain@10044060 {
 		compatible = "samsung,exynos4210-pd";
 		reg = <0x10044060 0x20>;
-		clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_SW_ACLK333>,
-			<&clock CLK_MOUT_USER_ACLK333>;
-		clock-names = "oscclk", "pclk0", "clk0";
+		clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_USER_ACLK333>;
+		clock-names = "oscclk", "clk0";
 		#power-domain-cells = <0>;
 	};