osquery: fix build

It seems as without the appropriate linker flag `-lcrypto` the
`libcrypto.sh` can't be found by `ld` which broke one of the linker
processes during compilation.

See also https://hydra.nixos.org/build/87208819

pkgs/tools/system/osquery/default.nix

@@ -39,6 +39,10 @@ stdenv.mkDerivation rec {
     pkgconfig cmake pythonPackages.python pythonPackages.jinja2 doxygen fpm
   ];
 
+  NIX_LDFLAGS = [
+    "-lcrypto"
+  ];
+
   buildInputs = let
     gflags' = google-gflags.overrideAttrs (old: {
       cmakeFlags = stdenv.lib.filter (f: isNull (builtins.match ".*STATIC.*" f)) old.cmakeFlags;