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/imx9/clock.c b/arch/arm/mach-imx/imx9/clock.c
index 12685f9..dda57ed 100644
--- a/arch/arm/mach-imx/imx9/clock.c
+++ b/arch/arm/mach-imx/imx9/clock.c
@@ -640,7 +640,7 @@
 	}
 }
 
-#ifdef CONFIG_SPL_BUILD
+#ifdef CONFIG_XPL_BUILD
 void dram_pll_init(ulong pll_val)
 {
 	configure_fracpll(DRAM_PLL_CLK, pll_val);
@@ -950,7 +950,7 @@
 /*
  * Dump some clockes.
  */
-#ifndef CONFIG_SPL_BUILD
+#ifndef CONFIG_XPL_BUILD
 int do_showclocks(struct cmd_tbl *cmdtp, int flag, int argc, char * const argv[])
 {
 	u32 freq;