common/Makefile: Compile fdt_support is enabled in SPL

When CONFIG_SPL_OF_TRANSLATE is enabled fdt_support.c needs to get
compiled. Otherwise fdt_translate_address() is missing which is needed
in dev_get_addr().

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/common/Makefile b/common/Makefile
index d8dc892..2a1d9f8 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -227,6 +227,7 @@
 obj-$(CONFIG_ENV_IS_IN_FLASH) += env_flash.o
 obj-$(CONFIG_SPL_YMODEM_SUPPORT) += xyzModem.o
 obj-$(CONFIG_SPL_NET_SUPPORT) += miiphyutil.o
+obj-$(CONFIG_SPL_OF_TRANSLATE) += fdt_support.o
 ifdef CONFIG_SPL_USB_HOST_SUPPORT
 obj-$(CONFIG_SPL_USB_SUPPORT) += usb.o usb_hub.o
 obj-$(CONFIG_USB_STORAGE) += usb_storage.o