Convert CONFIG_SYS_LOAD_ADDR to Kconfig

Now that we have consistent usage, migrate this symbol to Kconfig.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Rick Chen <rick@andestech.com>
diff --git a/configs/sama5d4ek_mmc_defconfig b/configs/sama5d4ek_mmc_defconfig
index 098e6ba..eaefb2d 100644
--- a/configs/sama5d4ek_mmc_defconfig
+++ b/configs/sama5d4ek_mmc_defconfig
@@ -23,6 +23,7 @@
 CONFIG_SPL_LIBDISK_SUPPORT=y
 CONFIG_DEBUG_UART=y
 CONFIG_ENV_VARS_UBOOT_CONFIG=y
+CONFIG_SYS_LOAD_ADDR=0x22000000
 CONFIG_FIT=y
 CONFIG_SD_BOOT=y
 CONFIG_BOOTDELAY=3