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-imx/imx8m/clock_imx8mm.c b/arch/arm/mach-imx/imx8m/clock_imx8mm.c
index d7fd102..d5745f6 100644
--- a/arch/arm/mach-imx/imx8m/clock_imx8mm.c
+++ b/arch/arm/mach-imx/imx8m/clock_imx8mm.c
@@ -51,7 +51,7 @@
 	return 0;
 }
 
-#ifdef CONFIG_SPL_BUILD
+#ifdef CONFIG_XPL_BUILD
 static struct imx_int_pll_rate_table imx8mm_fracpll_tbl[] = {
 	PLL_1443X_RATE(1000000000U, 250, 3, 1, 0),
 	PLL_1443X_RATE(933000000U, 311, 4, 1, 0),