board: tegra: convert boards to text env

Convert boards to use text based env. This is the first stage of
conversion, common inclusions should be converted next.

Acked-by: Francesco Dolcini <francesco.dolcini@toradex.com> # Toradex Apalis TK1
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
diff --git a/configs/qc750_defconfig b/configs/qc750_defconfig
index d0b07ee..58a3c83 100644
--- a/configs/qc750_defconfig
+++ b/configs/qc750_defconfig
@@ -5,6 +5,7 @@
 CONFIG_INITRD_TAG=y
 CONFIG_TEXT_BASE=0x80110000
 CONFIG_NR_DRAM_BANKS=2
+CONFIG_ENV_SOURCE_FILE="qc750"
 CONFIG_ENV_SIZE=0x3000
 CONFIG_ENV_OFFSET=0xFFFFD000
 CONFIG_DEFAULT_DEVICE_TREE="tegra30-wexler-qc750"