efi: Add ESRT to the EFI system table

The ESRT is initialised during efi_init_objlist after
efi_initialize_system_table().

The ESRT is recreated from scratch at the following events:
- successful UpdateCapsule;
- FMP instance install.

The code ensures that every ESRT entry has a unique fw_class value.

Limitations:
- The ESRT is not updated if an FMP instance is uninstalled;
- the fields image_type and flags are in the current implementation left
undefined. Setting these values will require a per-platform function
that returns the image_type/flags as a function of the image fw_class.

CC: Heinrich Schuchardt	<xypron.glpk@gmx.de>
CC: Sughosh Ganu <sughosh.ganu@linaro.org>
CC: AKASHI Takahiro <takahiro.akashi@linaro.org>
CC: Ilias Apalodimas <ilias.apalodimas@linaro.org>
CC: Andre Przywara <andre.przywara@arm.com>
CC: Alexander Graf <agraf@csgraf.de>
CC: nd@arm.com
Signed-off-by: Jose Marinho <jose.marinho@arm.com>

Remove two EFI_CALL() indirections.
Move ESRT GUID in efidebug's list of GUIDs.

Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

lib/efi_loader/efi_boottime.c

@@ -1406,10 +1406,9 @@ out:
  *
  * Return: status code
  */
-static efi_status_t EFIAPI efi_register_protocol_notify(
-						const efi_guid_t *protocol,
-						struct efi_event *event,
-						void **registration)
+efi_status_t EFIAPI efi_register_protocol_notify(const efi_guid_t *protocol,
+						 struct efi_event *event,
+						 void **registration)
 {
 	struct efi_register_notify_event *item;
 	efi_status_t ret = EFI_SUCCESS;