configs: move CONFIG_SPL_TEXT_BASE to Kconfig

Moved CONFIG_SPL_TEXT_BASE to common/spl/Kconfig and migrate existing
values.

Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
[trini: Re-run migration]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/MPC8313ERDB_NAND_66_defconfig b/configs/MPC8313ERDB_NAND_66_defconfig
index a454ec6..83f0f6d 100644
--- a/configs/MPC8313ERDB_NAND_66_defconfig
+++ b/configs/MPC8313ERDB_NAND_66_defconfig
@@ -11,6 +11,7 @@
 CONFIG_MISC_INIT_R=y
 CONFIG_BOARD_EARLY_INIT_R=y
 # CONFIG_SPL_FRAMEWORK is not set
+CONFIG_SPL_TEXT_BASE=0xFFF00000
 CONFIG_SPL_NAND_SUPPORT=y
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_IMLS=y