clk: st: Adds clockgen clock binding

Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

Documentation/devicetree/bindings/clock/st/st,clkgen-pll.txt

+Binding for a ST pll clock driver.
+
+This binding uses the common clock binding[1].
+Base address is located to the parent node. See clock binding[2]
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+[2] Documentation/devicetree/bindings/clock/st/st,clkgen.txt
+
+Required properties:
+
+- compatible : shall be:
+	"st,clkgena-prediv-c65",	"st,clkgena-prediv"
+	"st,clkgena-prediv-c32",	"st,clkgena-prediv"
+
+	"st,clkgena-plls-c65"
+	"st,plls-c32-a1x-0",		"st,clkgen-plls-c32"
+	"st,plls-c32-a1x-1",		"st,clkgen-plls-c32"
+	"st,stih415-plls-c32-a9",	"st,clkgen-plls-c32"
+	"st,stih415-plls-c32-ddr",	"st,clkgen-plls-c32"
+	"st,stih416-plls-c32-a9",	"st,clkgen-plls-c32"
+	"st,stih416-plls-c32-ddr",	"st,clkgen-plls-c32"
+
+	"st,stih415-gpu-pll-c32",	"st,clkgengpu-pll-c32"
+	"st,stih416-gpu-pll-c32",	"st,clkgengpu-pll-c32"
+
+
+- #clock-cells : From common clock binding; shall be set to 1.
+
+- clocks : From common clock binding
+
+- clock-output-names : From common clock binding.
+
+Example:
+
+	clockgenA@fee62000 {
+		reg = <0xfee62000 0xb48>;
+
+		CLK_S_A0_PLL: CLK_S_A0_PLL {
+			#clock-cells = <1>;
+			compatible = "st,clkgena-plls-c65";
+
+			clocks = <&CLK_SYSIN>;
+
+			clock-output-names = "CLK_S_A0_PLL0_HS",
+					     "CLK_S_A0_PLL0_LS",
+					     "CLK_S_A0_PLL1";
+		};
+	};