x86: Don't set up MTRRs in SPL

The MTRRs are normally set up in U-Boot proper, so avoid setting them up
in SPL as well.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>

arch/x86/lib/init_helpers.c

@@ -18,7 +18,10 @@ __weak ulong board_get_usable_ram_top(ulong total_size)
 
 int init_cache_f_r(void)
 {
-#if CONFIG_IS_ENABLED(X86_32BIT_INIT) && !defined(CONFIG_HAVE_FSP)
+#if (CONFIG_IS_ENABLED(X86_32BIT_INIT) || \
+     (!defined(CONFIG_SPL_BUILD) && \
+      !CONFIG_IS_ENABLED(CONFIG_X86_RUN_64BIT))) && \
+    !defined(CONFIG_HAVE_FSP)
 	int ret;
 
 	ret = mtrr_commit(false);