UEFI specification requires that we shall support three type of
certificates of authenticode in PE image:
WIN_CERT_TYPE_EFI_GUID with the guid, EFI_CERT_TYPE_PCKS7_GUID
WIN_CERT_TYPE_PKCS_SIGNED_DATA
WIN_CERT_TYPE_EFI_PKCS1_15
As EDK2 does, we will support the first two that are pkcs7 SignedData.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>