configs: Migrate CONFIG_SYS_TEXT_BASE

On the NIOS2 and Xtensa architectures, we do not have
CONFIG_SYS_TEXT_BASE set.  This is a strict migration of the current
values into the defconfig and removing them from the headers.

I did not attempt to add more default values in and for now will leave
that to maintainers.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/usb_a9263_dataflash_defconfig b/configs/usb_a9263_dataflash_defconfig
index a1b0a48..cec1e9c 100644
--- a/configs/usb_a9263_dataflash_defconfig
+++ b/configs/usb_a9263_dataflash_defconfig
@@ -1,5 +1,6 @@
 CONFIG_ARM=y
 CONFIG_ARCH_AT91=y
+CONFIG_SYS_TEXT_BASE=0x23f00000
 CONFIG_TARGET_USB_A9263=y
 CONFIG_SYS_MALLOC_F_LEN=0x2000
 CONFIG_DEFAULT_DEVICE_TREE="usb_a9263"