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/arm/mach-imx/spl.c b/arch/arm/mach-imx/spl.c
index ef00969..6b8f411 100644
--- a/arch/arm/mach-imx/spl.c
+++ b/arch/arm/mach-imx/spl.c
@@ -341,7 +341,7 @@
 	if (bl_len < 512)
 		bl_len = 512;
 
-	return  (void *)((CONFIG_SYS_TEXT_BASE - fit_size - bl_len -
+	return  (void *)((CONFIG_TEXT_BASE - fit_size - bl_len -
 			align_len) & ~align_len);
 }
 #endif