efi_loader: define UpdateCapsule api

In this commit, skeleton functions for capsule-related API's are
added under CONFIG_EFI_UPDATE_CAPSULE configuration.
Detailed implementation for a specific capsule type will be added
in the succeeding patches.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
diff --git a/include/efi_loader.h b/include/efi_loader.h
index 3c68b85..abd6856 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -210,6 +210,8 @@
 
 /* GUID of RNG protocol */
 extern const efi_guid_t efi_guid_rng_protocol;
+/* GUID of capsule update result */
+extern const efi_guid_t efi_guid_capsule_report;
 
 extern unsigned int __efi_runtime_start, __efi_runtime_stop;
 extern unsigned int __efi_runtime_rel_start, __efi_runtime_rel_stop;
@@ -812,6 +814,17 @@
 /* commonly used helper function */
 u16 *efi_create_indexed_name(u16 *buffer, const char *name, unsigned int index);
 
+/* Capsule update */
+efi_status_t EFIAPI efi_update_capsule(
+		struct efi_capsule_header **capsule_header_array,
+		efi_uintn_t capsule_count,
+		u64 scatter_gather_list);
+efi_status_t EFIAPI efi_query_capsule_caps(
+		struct efi_capsule_header **capsule_header_array,
+		efi_uintn_t capsule_count,
+		u64 *maximum_capsule_size,
+		u32 *reset_type);
+
 #else /* CONFIG_IS_ENABLED(EFI_LOADER) */
 
 /* Without CONFIG_EFI_LOADER we don't have a runtime section, stub it out */