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/qemu_arm64_defconfig b/configs/qemu_arm64_defconfig
index 4309bd2..cdf5072 100644
--- a/configs/qemu_arm64_defconfig
+++ b/configs/qemu_arm64_defconfig
@@ -1,6 +1,7 @@
 CONFIG_ARM=y
 CONFIG_ARM_SMCCC=y
 CONFIG_ARCH_QEMU=y
+CONFIG_SYS_TEXT_BASE=0x00000000
 CONFIG_TARGET_QEMU_ARM_64BIT=y
 CONFIG_AHCI=y
 CONFIG_DISTRO_DEFAULTS=y