Add private forwarding headers for `openssl/{evp,hmac}.h` to give us a
central place to add adaptation code to work across multiple
incompatible OpenSSL versions. Provide compatibility implementations of
some OpenSSL 1.1 APIs when using older OpenSSL versions.
Resolve conflicts in favor of the upstream side where possible.
Resolve a logical conflict in archive_windows.h where the upstream
port to Watcom was done slightly differently from ours.
Remove add_subdirectory() calls for directories not included in the
reduced libarchive snapshot. Remove options that configure settings in
the missing directories.
This allows for a built in bzip and zip capability, so external tools
will not be needed for these packagers. The cmake -E tar xf should be
able to handle all compression types now as well.