Detect out-of-spec size requirement for some FFS sections

[NikolajSchlej]

There is a small number of EFI images that treat UEFI specification incorrectly and instead of only ensuring that offsetof(FFS_section) % 4 == 0 ("FFS sections must be aligned to 4-byte boundary") they additionally ensure that sizeof(FFS_section) % 4 == 0 ("FFS section size is a multiple of 4").

This is fairly easy to detect (by checking for additional 1-3 bytes that are stored after the FFS section not having a size that's multiple of 4), and it needs to be preserved during rebuild (or the resulting image will crash in PeiCore/DxeCore because of buffer overflow).

• Detect out-of-spec size req. for FFS sections

[NikolajSchlej]

Found an image that has the issue, but it only has it for Tiano-compressed sections, so needs further investigation. I can implement a warning about such a case for non-compressed sections and see if anybody will ever catch it on a live image.

990K31_1.30.zip