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/pg_wcom_seli8_defconfig b/configs/pg_wcom_seli8_defconfig
index f21294f..a32fb6e 100644
--- a/configs/pg_wcom_seli8_defconfig
+++ b/configs/pg_wcom_seli8_defconfig
@@ -17,6 +17,7 @@
 CONFIG_SYS_BOOTCOUNT_ADDR=0x70000020
 CONFIG_AHCI=y
 CONFIG_DISTRO_DEFAULTS=y
+CONFIG_SYS_LOAD_ADDR=0x82000000
 CONFIG_FIT=y
 CONFIG_FIT_VERBOSE=y
 CONFIG_OF_BOARD_SETUP=y