efi_loader: log EFI return values too

Turns out this is rather useful to tracking down where things fail.

Signed-off-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/include/efi_loader.h b/include/efi_loader.h
index 4bcd35a..40f6c89 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -20,7 +20,10 @@
 	debug("EFI: Entry %s(" format ")\n", __func__, ##__VA_ARGS__); \
 	} while(0)
 
-#define EFI_EXIT(ret) efi_exit_func(ret);
+#define EFI_EXIT(ret) ({ \
+	debug("EFI: Exit: %s: %u\n", __func__, (u32)((ret) & ~EFI_ERROR_MASK)); \
+	efi_exit_func(ret); \
+	})
 
 extern struct efi_runtime_services efi_runtime_services;
 extern struct efi_system_table systab;