x86: Handle running as EFI payload

When U-Boot runs as an EFI payload it needs to avoid setting up the CPU
again. Also U-Boot currently does not handle interrupts for many devices, so
run with interrupts disabled.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
index a112938..9217307 100644
--- a/arch/x86/cpu/interrupts.c
+++ b/arch/x86/cpu/interrupts.c
@@ -258,8 +258,14 @@
 	/* Initialize core interrupt and exception functionality of CPU */
 	cpu_init_interrupts();
 
-	/* It is now safe to enable interrupts */
-	enable_interrupts();
+	/*
+	 * It is now safe to enable interrupts.
+	 *
+	 * TODO(sjg@chromium.org): But we don't handle these correctly when
+	 * booted from EFI.
+	 */
+	if (ll_boot_init())
+		enable_interrupts();
 #endif
 
 	return 0;