ARM: at91/dt: disable pull-up on vbus-gpio (PB16) to reduce power consumption

There is an external resistor divider on PB16, acting like a pull-down,
the pull-up increase power consumption and prevent the vbus detect pin
to reach Vss voltage, ~1.5V mesured on my board, it might not even work
if the pull-up is stronger than usual.
Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
Acked-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

arch/arm/boot/dts/at91sam9x5ek.dtsi

@@ -53,6 +53,8 @@ usart0: serial@f801c000 {
 			};
 
 			usb2: gadget@f803c000 {
+				pinctrl-names = "default";
+				pinctrl-0 = <&pinctrl_board_usb2>;
 				atmel,vbus-gpio = <&pioB 16 GPIO_ACTIVE_HIGH>;
 				status = "okay";
 			};
@@ -80,6 +82,13 @@ pinctrl_board_mmc1: mmc1-board {
 							<AT91_PIOD 14 AT91_PERIPH_GPIO AT91_PINCTRL_PULL_UP_DEGLITCH>;	/* PD14 gpio CD pin pull up and deglitch */
 					};
 				};
+
+				usb2 {
+					pinctrl_board_usb2: usb2-board {
+						atmel,pins =
+							<AT91_PIOB 16 AT91_PERIPH_GPIO AT91_PINCTRL_DEGLITCH>;		/* PB16 gpio vbus sense, deglitch */
+					};
+				};
 			};
 
 			spi0: spi@f0000000 {