global: Use CONFIG_XPL_BUILD instead of CONFIG_SPL_BUILD

Complete this rename for all directories outside arch/ board/ drivers/
and include/

Use the new symbol to refer to any 'SPL' build, including TPL and VPL

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/env/nand.c b/env/nand.c
index fef5697..fdaa903 100644
--- a/env/nand.c
+++ b/env/nand.c
@@ -26,9 +26,9 @@
 #include <u-boot/crc.h>
 
 #if defined(CONFIG_CMD_SAVEENV) && defined(CONFIG_CMD_NAND) && \
-		!defined(CONFIG_SPL_BUILD)
+		!defined(CONFIG_XPL_BUILD)
 #define CMD_SAVEENV
-#elif defined(CONFIG_ENV_OFFSET_REDUND) && !defined(CONFIG_SPL_BUILD)
+#elif defined(CONFIG_ENV_OFFSET_REDUND) && !defined(CONFIG_XPL_BUILD)
 #error CONFIG_ENV_OFFSET_REDUND must have CONFIG_CMD_SAVEENV & CONFIG_CMD_NAND
 #endif
 
@@ -224,7 +224,7 @@
 }
 #endif /* CMD_SAVEENV */
 
-#if defined(CONFIG_SPL_BUILD)
+#if defined(CONFIG_XPL_BUILD)
 static int readenv(size_t offset, u_char *buf)
 {
 	return nand_spl_load_image(offset, CONFIG_ENV_SIZE, buf);
@@ -265,7 +265,7 @@
 
 	return 0;
 }
-#endif /* #if defined(CONFIG_SPL_BUILD) */
+#endif /* #if defined(CONFIG_XPL_BUILD) */
 
 #ifdef CONFIG_ENV_OFFSET_OOB
 int get_nand_env_oob(struct mtd_info *mtd, unsigned long *result)