ARM: imx: add ocram clock for imx53

Add missing ocram gate clock for imx53 and also represent it in device
tree ocram node.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

Documentation/devicetree/bindings/clock/imx5-clock.txt

@@ -197,6 +197,7 @@ clocks and IDs.
 	spdif0_gate		183
 	spdif1_gate		184
 	spdif_ipg_gate		185
+	ocram			186
 
 Examples (for mx53):
 

arch/arm/boot/dts/imx53.dtsi

@@ -1121,6 +1121,7 @@
 		ocram: sram@f8000000 {
 			compatible = "mmio-sram";
 			reg = <0xf8000000 0x20000>;
+			clocks = <&clks 186>;
 		};
 	};
 };

arch/arm/mach-imx/clk-imx51-imx53.c

@@ -119,7 +119,7 @@ enum imx5_clks {
 	srtc_gate, pata_gate, sata_gate, spdif_xtal_sel, spdif0_sel,
 	spdif1_sel, spdif0_pred, spdif0_podf, spdif1_pred, spdif1_podf,
 	spdif0_com_s, spdif1_com_sel, spdif0_gate, spdif1_gate, spdif_ipg_gate,
-	clk_max
+	ocram, clk_max
 };
 
 static struct clk *clk[clk_max];
@@ -506,6 +506,7 @@ int __init mx53_clocks_init(unsigned long rate_ckil, unsigned long rate_osc,
 				mx53_can_sel, ARRAY_SIZE(mx53_can_sel));
 	clk[can1_serial_gate] = imx_clk_gate2("can1_serial_gate", "can_sel", MXC_CCM_CCGR6, 22);
 	clk[can1_ipg_gate] = imx_clk_gate2("can1_ipg_gate", "ipg", MXC_CCM_CCGR6, 20);
+	clk[ocram] = imx_clk_gate2("ocram", "ahb", MXC_CCM_CCGR6, 2);
 	clk[can2_serial_gate] = imx_clk_gate2("can2_serial_gate", "can_sel", MXC_CCM_CCGR4, 8);
 	clk[can2_ipg_gate] = imx_clk_gate2("can2_ipg_gate", "ipg", MXC_CCM_CCGR4, 6);
 	clk[i2c3_gate] = imx_clk_gate2("i2c3_gate", "per_root", MXC_CCM_CCGR1, 22);