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/board/beacon/beacon-rzg2m/beacon-rzg2m.c b/board/beacon/beacon-rzg2m/beacon-rzg2m.c
index 4b41c6f..99fe1ed 100644
--- a/board/beacon/beacon-rzg2m/beacon-rzg2m.c
+++ b/board/beacon/beacon-rzg2m/beacon-rzg2m.c
@@ -12,7 +12,7 @@
 int board_init(void)
 {
 	/* address of boot parameters */
-	gd->bd->bi_boot_params = CONFIG_SYS_TEXT_BASE + 0x50000;
+	gd->bd->bi_boot_params = CONFIG_TEXT_BASE + 0x50000;
 
 	return 0;
 }