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/socfpga_dbm_soc1_defconfig b/configs/socfpga_dbm_soc1_defconfig
index 233d133..dd14be4 100644
--- a/configs/socfpga_dbm_soc1_defconfig
+++ b/configs/socfpga_dbm_soc1_defconfig
@@ -10,6 +10,7 @@
 CONFIG_VERSION_VARIABLE=y
 # CONFIG_DISPLAY_BOARDINFO is not set
 CONFIG_DISPLAY_BOARDINFO_LATE=y
+CONFIG_SPL_TEXT_BASE=0xFFFF0000
 CONFIG_SPL_SPI_LOAD=y
 CONFIG_HUSH_PARSER=y
 CONFIG_CMD_BOOTZ=y