arm64: dts: imx8mq-hummingboard-pulse: Align pin configuration group names with schema

Device tree schema expects pin configuration groups to end with 'grp'
suffix, otherwise dtbs_check complain with a warning like:

    ... do not match any of the regexes: 'grp$', 'pinctrl-[0-9]+'
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq-hummingboard-pulse.dts

@@ -214,13 +214,13 @@ MX8MQ_IOMUXC_UART3_RXD_UART3_DCE_RX		0x49
 		>;
 	};
 
-	pinctrl_usdhc2_gpio: usdhc2grpgpio {
+	pinctrl_usdhc2_gpio: usdhc2gpiogrp {
 		fsl,pins = <
 			MX8MQ_IOMUXC_SD2_CD_B_GPIO2_IO12	0x41
 		>;
 	};
 
-	pinctrl_usdhc2_vmmc: usdhc2vmmcgpio {
+	pinctrl_usdhc2_vmmc: usdhc2vmmcgpiogrp {
 		fsl,pins = <
 			MX8MQ_IOMUXC_GPIO1_IO13_GPIO1_IO13	0x41
 		>;
@@ -238,7 +238,7 @@ MX8MQ_IOMUXC_GPIO1_IO04_USDHC2_VSELECT		0xc1
 		>;
 	};
 
-	pinctrl_usdhc2_100mhz: usdhc2grp100mhz {
+	pinctrl_usdhc2_100mhz: usdhc2-100mhzgrp {
 		fsl,pins = <
 			MX8MQ_IOMUXC_SD2_CLK_USDHC2_CLK			0x8d
 			MX8MQ_IOMUXC_SD2_CMD_USDHC2_CMD			0xcd
@@ -250,7 +250,7 @@ MX8MQ_IOMUXC_GPIO1_IO04_USDHC2_VSELECT		0xc1
 		>;
 	};
 
-	pinctrl_usdhc2_200mhz: usdhc2grp200mhz {
+	pinctrl_usdhc2_200mhz: usdhc2-200mhzgrp {
 		fsl,pins = <
 			MX8MQ_IOMUXC_SD2_CLK_USDHC2_CLK			0x9f
 			MX8MQ_IOMUXC_SD2_CMD_USDHC2_CMD			0xdf