ARM: dts: imx6q-logicpd: Add missing imx6q-logicpd-u-boot for SPL

The SPL device tree is missing the entires for gpio1, uart1, usdhc1 and
usdhc2.  This creates the missing imx6q-logicpd-u-boot.dtsi file
which will enable these functions so SPL can properly setup UART, detect
microSD card, and startup.

Fixes: 8f4691e31a18 ("ARM: imx6q_logic: With SPL_OF_CONTROL enabled,
remove MMC init")

Signed-off-by: Adam Ford <aford173@gmail.com>
diff --git a/board/logicpd/imx6/MAINTAINERS b/board/logicpd/imx6/MAINTAINERS
index 20ec591..4280315 100644
--- a/board/logicpd/imx6/MAINTAINERS
+++ b/board/logicpd/imx6/MAINTAINERS
@@ -7,3 +7,4 @@
 F:     arch/arm/dts/imx6-logicpd-baseboard.dtsi
 F:     arch/arm/dts/imx6-logicpd-som.dtsi
 F:     arch/arm/dts/imx6q-logicpd.dts
+F:     arch/arm/dts/imx6q-logicpd-u-boot.dtsi