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/Kconfig b/lib/efi_loader/Kconfig
index 23ba065..13e7930 100644
--- a/lib/efi_loader/Kconfig
+++ b/lib/efi_loader/Kconfig
@@ -127,6 +127,14 @@
 	  executed as part of U-Boot initialisation so that they will
 	  surely take place whatever is set to distro_bootcmd.
 
+config EFI_CAPSULE_FIRMWARE_MANAGEMENT
+	bool "Capsule: Firmware Management Protocol"
+	depends on EFI_HAVE_CAPSULE_SUPPORT
+	default y
+	help
+	  Select this option if you want to enable capsule-based
+	  firmware update using Firmware Management Protocol.
+
 config EFI_DEVICE_PATH_TO_TEXT
 	bool "Device path to text protocol"
 	default y