rockchip: rk3399-puma: remove default value from defconfig

CONFIG_ENV_OFFSET already defaults to 0x3F8000, however it is stored in
lowercase hexdigits instead of uppercase like in the defconfig.

No change in behavior intended.

Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Signed-off-by: Quentin Schulz <quentin.schulz@cherry.de>
diff --git a/configs/puma-rk3399_defconfig b/configs/puma-rk3399_defconfig
index 34a0b57..4281910 100644
--- a/configs/puma-rk3399_defconfig
+++ b/configs/puma-rk3399_defconfig
@@ -6,7 +6,6 @@
 CONFIG_NR_DRAM_BANKS=1
 CONFIG_SF_DEFAULT_SPEED=20000000
 CONFIG_ENV_SIZE=0x3000
-CONFIG_ENV_OFFSET=0x3F8000
 CONFIG_DEFAULT_DEVICE_TREE="rockchip/rk3399-puma-haikou"
 CONFIG_DM_RESET=y
 CONFIG_ROCKCHIP_RK3399=y