pico-imx7d: Allow default fdtfile to be overridden by defconfig

This allow the addition of extra default configurations for each
baseboard, removing the boot menu when user boots for the first time.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
diff --git a/configs/pico-imx7d_defconfig b/configs/pico-imx7d_defconfig
index 17fe13b..af2a776 100644
--- a/configs/pico-imx7d_defconfig
+++ b/configs/pico-imx7d_defconfig
@@ -14,6 +14,7 @@
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=arch/arm/mach-imx/spl_sd.cfg"
 CONFIG_BOOTCOMMAND="run findfdt; run finduuid; run distro_bootcmd"
+CONFIG_DEFAULT_FDT_FILE="ask"
 CONFIG_SPL_I2C_SUPPORT=y
 CONFIG_SPL_USB_HOST_SUPPORT=y
 CONFIG_SPL_USB_GADGET_SUPPORT=y
diff --git a/include/configs/pico-imx7d.h b/include/configs/pico-imx7d.h
index 8f1876c..13e7353 100644
--- a/include/configs/pico-imx7d.h
+++ b/include/configs/pico-imx7d.h
@@ -65,7 +65,7 @@
 	"console=ttymxc4\0" \
 	"fdt_high=0xffffffff\0" \
 	"initrd_high=0xffffffff\0" \
-	"fdtfile=ask\0" \
+	"fdtfile=" CONFIG_DEFAULT_FDT_FILE "\0" \
 	BOOTMENU_ENV \
 	"fdt_addr=0x83000000\0" \
 	"fdt_addr_r=0x83000000\0" \