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/arch/mips/mach-jz47xx/jz4780/jz4780.c b/arch/mips/mach-jz47xx/jz4780/jz4780.c
index 4c40bd8..cff98b0 100644
--- a/arch/mips/mach-jz47xx/jz4780/jz4780.c
+++ b/arch/mips/mach-jz47xx/jz4780/jz4780.c
@@ -58,7 +58,7 @@
 	if (ret)
 		hang();
 
-	header = (struct legacy_img_hdr *)(CONFIG_SYS_TEXT_BASE -
+	header = (struct legacy_img_hdr *)(CONFIG_TEXT_BASE -
 					 sizeof(struct legacy_img_hdr));
 
 	count = blk_dread(mmc_get_blk_desc(mmc),
@@ -68,7 +68,7 @@
 		hang();
 
 	image_entry_noargs_t image_entry =
-		(image_entry_noargs_t)CONFIG_SYS_TEXT_BASE;
+		(image_entry_noargs_t)CONFIG_TEXT_BASE;
 
 	image_entry();