include: 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/include/configs/imx8mm_phg.h b/include/configs/imx8mm_phg.h
index d2d7ffa..038d3a7 100644
--- a/include/configs/imx8mm_phg.h
+++ b/include/configs/imx8mm_phg.h
@@ -14,7 +14,7 @@
 #define CFG_SYS_UBOOT_BASE	\
 	(QSPI0_AMBA_BASE + CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR * 512)
 
-#ifdef CONFIG_SPL_BUILD
+#ifdef CONFIG_XPL_BUILD
 /* malloc f used before GD_FLG_FULL_MALLOC_INIT set */
 #define CFG_MALLOC_F_ADDR		0x930000
 #endif