config: Move CONFIG_DEFAULT_FDT_FILE to defconfigs

- Add DEFAULT_FDT_FILE kconfig entry
- Move CONFIG_DEFAULT_FDT_FILE from include/configs to defconfigs

Cc: Tom Rini <trini@konsulko.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/configs/tqma6s_mba6_mmc_defconfig b/configs/tqma6s_mba6_mmc_defconfig
index 426b4c0..33436fc 100644
--- a/configs/tqma6s_mba6_mmc_defconfig
+++ b/configs/tqma6s_mba6_mmc_defconfig
@@ -5,6 +5,7 @@
 CONFIG_FIT=y
 CONFIG_FIT_VERBOSE=y
 CONFIG_OF_BOARD_SETUP=y
+CONFIG_DEFAULT_FDT_FILE="imx6dl-mba6x.dtb"
 CONFIG_BOOTDELAY=3
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_BOOTZ=y