Rename CONFIG_SYS_TEXT_BASE to CONFIG_TEXT_BASE

The current name is inconsistent with SPL which uses CONFIG_SPL_TEXT_BASE
and this makes it imposible to use CONFIG_VAL().

Rename it to resolve this problem.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/rpi_3_32b_defconfig b/configs/rpi_3_32b_defconfig
index 0ffb466..f51f3de 100644
--- a/configs/rpi_3_32b_defconfig
+++ b/configs/rpi_3_32b_defconfig
@@ -2,7 +2,7 @@
 CONFIG_SKIP_LOWLEVEL_INIT=y
 CONFIG_ARCH_CPU_INIT=y
 CONFIG_ARCH_BCM283X=y
-CONFIG_SYS_TEXT_BASE=0x00008000
+CONFIG_TEXT_BASE=0x00008000
 CONFIG_TARGET_RPI_3_32B=y
 CONFIG_NR_DRAM_BANKS=1
 CONFIG_ENV_SIZE=0x4000