Build the Compress::Raw::Zlib perl module with /usr/lib/libz

Build the Compress::Raw::Zlib perl module with /usr/lib/libz

Two actively used copies of zlib in base are enough. This simplifies
handling security fixes. Now that zlib.h r1.7 is reverted, zlib ffi
works fine on 32-bit architectures.

Compared with an earlier attempt in March, this disables the Z_SOLO build
option (problem found by gkoehler) and fixes two regress tests to work
with zlib 1.2.12. Corresponding upstream commits:
https://github.com/pmqs/Compress-Raw-Zlib/commit/c44e0b732e214b7f77d42a3af6ae64e
https://github.com/pmqs/Compress-Raw-Zlib/commit/f47ea5f36c40fe19efe404dd75fd790

ok bluhm