sunxi: Add environment settings to make extlinux.conf booting work

Automatic booting using an extlinux.conf file requires various environment
variables to be set.

Also modify CONFIG_SYS_LOAD_ADDR and CONFIG_STANDALONE_LOAD_ADDR to match
the value chosen for kernel_addr_r, see the added comment for why the new
value is chosen.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
diff --git a/configs/A10s-OLinuXino-M_defconfig b/configs/A10s-OLinuXino-M_defconfig
index 1560ab1..f206970 100644
--- a/configs/A10s-OLinuXino-M_defconfig
+++ b/configs/A10s-OLinuXino-M_defconfig
@@ -1,4 +1,5 @@
 CONFIG_SPL=y
 CONFIG_SYS_EXTRA_OPTIONS="A10S_OLINUXINO_M,SPL,AXP152_POWER,SUNXI_EMAC,USB_EHCI,SUNXI_USB_VBUS0_GPIO=SUNXI_GPB(10)"
+CONFIG_FTDFILE="sun5i-a10s-olinuxino-micro.dtb"
 +S:CONFIG_ARM=y
 +S:CONFIG_TARGET_SUN5I=y