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/x530_defconfig b/configs/x530_defconfig
index c4b0a00..7db8de4 100644
--- a/configs/x530_defconfig
+++ b/configs/x530_defconfig
@@ -19,6 +19,7 @@
 CONFIG_SILENT_U_BOOT_ONLY=y
 CONFIG_SILENT_CONSOLE_UPDATE_ON_RELOC=y
 CONFIG_MISC_INIT_R=y
+CONFIG_SPL_TEXT_BASE=0x40000030
 CONFIG_SPL_BOARD_INIT=y
 CONFIG_SPL_WATCHDOG_SUPPORT=y
 CONFIG_CMD_MEMINFO=y