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-sunxi/board.c b/arch/arm/mach-sunxi/board.c
index 220ed80..8623363 100644
--- a/arch/arm/mach-sunxi/board.c
+++ b/arch/arm/mach-sunxi/board.c
@@ -363,7 +363,7 @@
 static bool sunxi_valid_emmc_boot(struct mmc *mmc)
 {
 	struct blk_desc *bd = mmc_get_blk_desc(mmc);
-	uint32_t *buffer = (void *)(uintptr_t)CONFIG_SYS_TEXT_BASE;
+	u32 *buffer = (void *)(uintptr_t)CONFIG_TEXT_BASE;
 	struct boot_file_head *egon_head = (void *)buffer;
 	int bootpart = EXT_CSD_EXTRACT_BOOT_PART(mmc->part_config);
 	uint32_t spl_size, emmc_checksum, chksum = 0;