board: 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/board/logicpd/am3517evm/am3517evm.c b/board/logicpd/am3517evm/am3517evm.c
index e6ca310..e4f619d 100644
--- a/board/logicpd/am3517evm/am3517evm.c
+++ b/board/logicpd/am3517evm/am3517evm.c
@@ -39,7 +39,7 @@
 #define CPGMACSS_SW_RST		(1 << 1)
 #define PHY_GPIO		30
 
-#if defined(CONFIG_SPL_BUILD)
+#if defined(CONFIG_XPL_BUILD)
 #if defined(CONFIG_SPL_OS_BOOT)
 int spl_start_uboot(void)
 {