* kern/efi/efi.c: Include grub/efi/pe32.h and grub/kernel.h.
(grub_efi_loaded_image_guid): New variable.
(grub_efi_get_loaded_image): New function.
(grub_arch_modules_addr): Likewise.
* include/grub/efi/efi.h (grub_efi_get_loaded_image): New
prototype.
* include/grub/efi/api.h (GRUB_EFI_LOADED_IMAGE_GUID): New macro.
(struct grub_efi_loaded_image): New structure.
(grub_efi_loaded_image_t): New type.