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/cortina_presidio-asic-pnand_defconfig b/configs/cortina_presidio-asic-pnand_defconfig
index a865cbf..b1c5069 100644
--- a/configs/cortina_presidio-asic-pnand_defconfig
+++ b/configs/cortina_presidio-asic-pnand_defconfig
@@ -7,6 +7,7 @@
 CONFIG_DM_GPIO=y
 CONFIG_DEFAULT_DEVICE_TREE="ca-presidio-engboard"
 CONFIG_IDENT_STRING="Presidio-SoC"
+CONFIG_SYS_LOAD_ADDR=0x10000000
 CONFIG_SHOW_BOOT_PROGRESS=y
 CONFIG_BOOTDELAY=3
 CONFIG_USE_BOOTARGS=y