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/uniphier_v8_defconfig b/configs/uniphier_v8_defconfig
index e862776f..946665b 100644
--- a/configs/uniphier_v8_defconfig
+++ b/configs/uniphier_v8_defconfig
@@ -9,6 +9,7 @@
 CONFIG_DEFAULT_DEVICE_TREE="uniphier-ld20-ref"
 CONFIG_ARCH_UNIPHIER_V8_MULTI=y
 CONFIG_MICRO_SUPPORT_CARD=y
+CONFIG_SYS_LOAD_ADDR=0x85000000
 # CONFIG_ARCH_FIXUP_FDT_MEMORY is not set
 CONFIG_BOOTCOMMAND="run ${bootdev}script; run ${bootdev}boot"
 CONFIG_USE_PREBOOT=y