packages depending on poppler broken on netbsd-9

[nia <nia%NetBSD.org@localhost>]

Packages depending on Poppler are failing to build on NetBSD 9:

https://releng.netbsd.org/pkgreports/shadow/HEAD/NetBSD-9.0-x86_64/20250411.0416/gimp-2.10.38nb13/build.log

ld: /pbulk/work/graphics/gimp/work/.buildlink/lib/libpoppler-glib.so: undefined reference to `std::__throw_bad_array_new_length()@GLIBCXX_3.4.29'
ld: /usr/pkg/lib/libpoppler.so.142: undefined reference to `std::condition_variable::wait(std::unique_lock<std::mutex>&)@GLIBCXX_3.4.30'
ld: /usr/pkg/lib/libpoppler.so.142: undefined reference to `std::__exception_ptr::exception_ptr::_M_addref()@CXXABI_1.3.13'

This is due to issues mixing libstdc++ versions.

Please, be careful updating libraries written in C++.

While it's okay to bump USE_CXX_FEATURES to whatever high version
for leaf packages and tools, with shared libraries problems will
appear.