Remove private/static markers from the pkg-config file

Remove private/static markers from the pkg-config file

Forwarded: not-needed
Origin: vendor
Last-Update: 2023-06-21

The pkg-config file lists as as private the internal libraries used by exiv2.
The problem is that those private markers require the availability of those
other pkg-config files to make exiv2.pc usable; since those are needed only
for static linking, and that there are no static libraries, simply delete them
to make exiv2.pc usable again.

This was forwarded upstream in a cleaner way together with the changes in the
CMake config files, and the changes affecting the pkg-config file were
rejected: https://github.com/Exiv2/exiv2/pull/2872

Gbp-Pq: Name pkgconfig-no-private.diff