mk: prefert inplace library paths to system ones

The link failure happens on a system with stable nix-2.3.15
installed in /usr/lib64 (it's libutil.so API differs from master):

```
LANG=C make V=1
g++ -o /home/slyfox/dev/git/nix/src/libstore/libnixstore.so \
    -shared -L/usr/lib64 -Wl,--no-copy-dt-needed-entries \
    src/libstore/binary-cache-store.o ... src/libstore/uds-remote-store.o \
    -lsqlite3 -lcurl -lsodium -pthread -ldl -lseccomp -Wl,-z,defs -Wl,-soname=libnixstore.so
      -Wl,-rpath,/home/slyfox/dev/git/nix/src/libutil -Lsrc/libutil -lnixutil
ld: src/libstore/binary-cache-store.o: in function `nix::BinaryCacheStore::BinaryCacheStore(
    std::map<std::__cxx11::basic_string<char, std::char_traits<char>, ...
nix/src/libstore/binary-cache-store.cc:30: undefined reference to `nix::readFile(
    std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' ...
...
```

This happens due to `-L/usr/lib64 -Lsrc/libutil` search path ordering.
The change turns it into `-Lsrc/libutil -L/usr/lib64`.

Closes: https://github.com/NixOS/nix/issues/3087

0 files changed, 0 insertions, 0 deletions