efi_loader: capsule: support firmware update

A capsule tagged with the guid, EFI_FIRMWARE_MANAGEMENT_CAPSULE_ID_GUID,
is handled as a firmware update object.
What efi_update_capsule() basically does is to load any firmware management
protocol (or fmp) drivers contained in a capsule, find out an appropriate
fmp driver and then invoke its set_image() interface against each binary
in a capsule.
In this commit, however, loading drivers is not supported.

The result of applying a capsule is set to be stored in "CapsuleXXXX"
variable, but its implementation is deferred to a fmp driver.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
index a126a59..ce6292f 100644
--- a/lib/efi_loader/efi_setup.c
+++ b/lib/efi_loader/efi_setup.c
@@ -159,6 +159,10 @@
 		os_indications_supported |=
 			EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED;
 
+	if (IS_ENABLED(CONFIG_EFI_CAPSULE_FIRMWARE_MANAGEMENT))
+		os_indications_supported |=
+			EFI_OS_INDICATIONS_FMP_CAPSULE_SUPPORTED;
+
 	return efi_set_variable_int(L"OsIndicationsSupported",
 				    &efi_global_variable_guid,
 				    EFI_VARIABLE_BOOTSERVICE_ACCESS |