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/kmtepr2_defconfig b/configs/kmtepr2_defconfig
index 8b0ac4b..4c5509b 100644
--- a/configs/kmtepr2_defconfig
+++ b/configs/kmtepr2_defconfig
@@ -139,6 +139,7 @@
 CONFIG_ACR_PARKM_USB_I2C1_BOOT=y
 CONFIG_LCRR_EADC_1=y
 CONFIG_LCRR_CLKDIV_2=y
+CONFIG_SYS_LOAD_ADDR=0x100000
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_OF_STDOUT_VIA_ALIAS=y
 CONFIG_AUTOBOOT_KEYED=y