x86: spl: Use hang() instead of a while() loop

Use the standard hang() function when booting fails since this implements
the defined U-Boot behaviour for this situation.

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 5d5d1a9..01a96d2 100644
--- a/arch/x86/lib/spl.c
+++ b/arch/x86/lib/spl.c
@@ -183,8 +183,7 @@
 	printf("Jumping to 64-bit U-Boot: Note many features are missing\n");
 	ret = cpu_jump_to_64bit_uboot(spl_image->entry_point);
 	debug("ret=%d\n", ret);
-	while (1)
-		;
+	hang();
 }
 #endif