src: use LIBC_SO and LIBNSL_SO from GNU libc, if available
This is from: https://bugzilla.samba.org/show_bug.cgi?id=10572#c17
See also: socket_wrapper@0fa56909
We use it in Debian's nss-wrapper package.
This is from: https://bugzilla.samba.org/show_bug.cgi?id=10572#c17
See also: socket_wrapper@0fa56909
We use it in Debian's nss-wrapper package.