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-davinci/misc.c b/arch/arm/mach-davinci/misc.c
index 6c97e58..07125ea 100644
--- a/arch/arm/mach-davinci/misc.c
+++ b/arch/arm/mach-davinci/misc.c
@@ -21,7 +21,7 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-#ifndef CONFIG_SPL_BUILD
+#ifndef CONFIG_XPL_BUILD
 int dram_init(void)
 {
 	/* dram_init must store complete ramsize in gd->ram_size */