board: turris_mox: Fixup U-Boot's device tree if PCIe connected

If PCIe Mox module is connected we want to have PCIe node enabled
in U-Boot's device tree.

Signed-off-by: Marek Behun <marek.behun@nic.cz>
Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/configs/turris_mox_defconfig b/configs/turris_mox_defconfig
index fb13b7e..6463abc 100644
--- a/configs/turris_mox_defconfig
+++ b/configs/turris_mox_defconfig
@@ -13,6 +13,7 @@
 # CONFIG_DISPLAY_CPUINFO is not set
 # CONFIG_DISPLAY_BOARDINFO is not set
 CONFIG_ARCH_EARLY_INIT_R=y
+CONFIG_OF_BOARD_FIXUP=y
 CONFIG_CMD_CLK=y
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_I2C=y