Commits
351d12437 ("nixos/release-notes: PHP config-file-scan-dir /etc -> /etc/php.d")
41c8aa8d6 ("php: change config-file-scan-dir from /etc to /etc/php.d")
were merged to master _after_ NixOS 16.09. Commit 351d12437 then wrongly
updated the NixSO 16.09 release notes. Fix by moving the entry to NixOS
17.03.