efi: Use asmlinkage for EFIAPI

This is required for x86 and is also correct for ARM (since it is empty).

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

include/efi.h

@@ -15,6 +15,7 @@
 #ifndef _EFI_H
 #define _EFI_H
 
+#include <linux/linkage.h>
 #include <linux/string.h>
 #include <linux/types.h>
 
@@ -22,7 +23,7 @@
 /* EFI uses the Microsoft ABI which is not the default for GCC */
 #define EFIAPI __attribute__((ms_abi))
 #else
-#define EFIAPI
+#define EFIAPI asmlinkage
 #endif
 
 struct efi_device_path;