ARM: at91: at91sam9x5: add clocks for usb device

Add clocks for usb device, or else switch to CCF, the gadget
won't work.
Reported-by: Jiri Prchal <jiri.prchal@aksignal.cz>
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Tested-by: Jiri Prchal <jiri.prchal@aksignal.cz>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/boot/dts/at91sam9x5.dtsi

@@ -1045,6 +1045,8 @@ usb2: gadget@f803c000 {
 				reg = <0x00500000 0x80000
 				       0xf803c000 0x400>;
 				interrupts = <23 IRQ_TYPE_LEVEL_HIGH 0>;
+				clocks = <&usb>, <&udphs_clk>;
+				clock-names = "hclk", "pclk";
 				status = "disabled";
 
 				ep0 {