x86: spl: Change the condition for copying U-Boot to RAM

Make this depend on whether the address matches the offset, rather than
a particular board build. For samus_tpl we don't need to copy, for
example.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/lib/spl.c b/arch/x86/lib/spl.c
index 58fa572..335dacf 100644
--- a/arch/x86/lib/spl.c
+++ b/arch/x86/lib/spl.c
@@ -258,7 +258,7 @@
 	spl_image->os = IH_OS_U_BOOT;
 	spl_image->name = "U-Boot";
 
-	if (!IS_ENABLED(CONFIG_SYS_COREBOOT)) {
+	if (spl_image->load_addr != spl_get_image_pos()) {
 		/* Copy U-Boot from ROM */
 		memcpy((void *)spl_image->load_addr,
 		       (void *)spl_get_image_pos(), spl_get_image_size());