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/openrd_base_defconfig b/configs/openrd_base_defconfig
index f91e0f9..75ebb22 100644
--- a/configs/openrd_base_defconfig
+++ b/configs/openrd_base_defconfig
@@ -1,6 +1,7 @@
 CONFIG_ARM=y
 CONFIG_SYS_THUMB_BUILD=y
 CONFIG_KIRKWOOD=y
+CONFIG_SYS_TEXT_BASE=0x600000
 CONFIG_TARGET_OPENRD=y
 CONFIG_IDENT_STRING="\nOpenRD-Base"
 CONFIG_SYS_EXTRA_OPTIONS="BOARD_IS_OPENRD_BASE"