configs: stm32: Enable CONFIG_ENV_VARS_UBOOT_CONFIG

Enable CONFIG_ENV_VARS_UBOOT_CONFIG for all STM32 boards
It allows to retrieve the SoC name into the "soc" environment
variable.

Signed-off-by: Christophe Priouzeau <christophe.priouzeau@st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Vikas Manocha <vikas.manocha@st.com>
diff --git a/include/configs/stm32f429-evaluation.h b/include/configs/stm32f429-evaluation.h
index ab33d0f..79b77bd 100644
--- a/include/configs/stm32f429-evaluation.h
+++ b/include/configs/stm32f429-evaluation.h
@@ -52,6 +52,7 @@
 #define CONFIG_BOOTCOMMAND						\
 	"run boot_sd"
 
+#define CONFIG_ENV_VARS_UBOOT_CONFIG
 #define CONFIG_EXTRA_ENV_SETTINGS \
 	"boot_sd=mmc dev 0;fatload mmc 0 0x00700000 stm32429i-eval.dtb; fatload mmc 0 0x00008000 zImage; icache off; bootz 0x00008000 - 0x00700000"