arch: Use CONFIG_XPL_BUILD instead of CONFIG_SPL_BUILD

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/arch/arm/mach-rockchip/rk3066/rk3066.c b/arch/arm/mach-rockchip/rk3066/rk3066.c
index 70b55ca..b8c177a 100644
--- a/arch/arm/mach-rockchip/rk3066/rk3066.c
+++ b/arch/arm/mach-rockchip/rk3066/rk3066.c
@@ -27,7 +27,7 @@
 
 void spl_board_init(void)
 {
-	if (!IS_ENABLED(CONFIG_SPL_BUILD))
+	if (!IS_ENABLED(CONFIG_XPL_BUILD))
 		return;
 
 	if (IS_ENABLED(CONFIG_SPL_DM_MMC)) {