uboot-phytec

efi_loader: correct a definition of struct efi_capsule_header

See UEFI specification, section 8.5.3.
In addition, the structure, efi_capsule_header, should be "packed"
as it is a serialized binary format in a capsule file.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>