ARM: dts: am437x-gp-evm: Add pinmux for gpio0 wake

Add pinctrl settings so that gpio0 wake from suspend will be supported
using buttons SW4 and SW7. Also, add pinctrl configuration for 0x954,
spi0_d0, which is an unused pin brought out to a header on the board
that in it's default state also connects to the gpio used for wakeup,
gpio0_3, which affects the state of the pin and prevents a working
wakeup unless we set the mux to a different state.
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am437x-gp-evm.dts

@@ -67,7 +67,13 @@ matrix_keypad: matrix_keypad0 {
 		debounce-delay-ms = <5>;
 		col-scan-delay-us = <2>;
 
-		row-gpios = <&gpio3 21 GPIO_ACTIVE_HIGH /* Bank3, pin21 */
+		pinctrl-names = "default", "sleep";
+		pinctrl-0 = <&matrix_keypad_default>;
+		pinctrl-1 = <&matrix_keypad_sleep>;
+
+		linux,wakeup;
+
+		row-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH /* Bank0, pin3 */
 				&gpio4 3 GPIO_ACTIVE_HIGH /* Bank4, pin3 */
 				&gpio4 2 GPIO_ACTIVE_HIGH>; /* Bank4, pin2 */
 
@@ -601,6 +607,24 @@ AM4372_IOPAD(0x970, PIN_INPUT_PULLUP | SLEWCTRL_FAST | DS0_PULL_UP_DOWN_EN | MUX
 			AM4372_IOPAD(0x974, PIN_INPUT_PULLDOWN | SLEWCTRL_FAST | DS0_PULL_UP_DOWN_EN | MUX_MODE0) /* uart0_txd.uart0_txd */
 		>;
 	};
+
+	matrix_keypad_default: matrix_keypad_default {
+		pinctrl-single,pins = <
+			AM4372_IOPAD(0x9a4, PIN_OUTPUT | MUX_MODE7)
+			AM4372_IOPAD(0x9a8, PIN_OUTPUT | MUX_MODE7)
+			AM4372_IOPAD(0x9ac, PIN_INPUT | PULL_DISABLE | MUX_MODE9)
+			AM4372_IOPAD(0x954, PIN_INPUT_PULLDOWN | MUX_MODE0)
+		>;
+	};
+
+	matrix_keypad_sleep: matrix_keypad_sleep {
+		pinctrl-single,pins = <
+			AM4372_IOPAD(0x9a4, PULL_UP | MUX_MODE7)
+			AM4372_IOPAD(0x9a8, PULL_UP | MUX_MODE7)
+			AM4372_IOPAD(0x9ac, PIN_INPUT | PULL_DISABLE | MUX_MODE9)
+			AM4372_IOPAD(0x954, PIN_INPUT_PULLDOWN | MUX_MODE0)
+		>;
+	};
 };
 
 &uart0 {