[ObjCopy] Respect requirements of LC_ENCRYPTION_INFO commands (#120995)
LLD (and other Mach-O linkers) when preparing an encryptable binary make
space to leave all the load commands in an non-encrypted page (see [1])
When using objcopy of a small encryptable binary, the code was not
respecting this fact, and the encryptable segments were not kept beyond
the first page. This was obvious for small or empty binaries.
The changes introduced here keep track if a `LC_ENCRYPTION_INFO` or
`LC_ENCRYPTION_INFO_64` has been seen, and in such case, it adds a full
page of offset in order to leave the load commands in its own page
(similar to what LLD is doing).
[1]:
https://github.com/llvm/llvm-project/blob/d8e792931226b15d9d2424ecd24ccfe13adc2367/lld/MachO/SyntheticSections.cpp#L90-L93