unbound: disable lto on static builds (PR #96020)

Signed-off-by: Arthur Gautier <baloo@superbaloo.net>

Amended by vcunat (isMusl != isStatic).
https://github.com/NixOS/nixpkgs/pull/96223#issuecomment-681204478

pkgs/tools/networking/unbound/default.nix

@@ -30,6 +30,8 @@ stdenv.mkDerivation rec {
     "--with-rootkey-file=${dns-root-data}/root.key"
     "--enable-pie"
     "--enable-relro-now"
+  ] ++ stdenv.lib.optional stdenv.hostPlatform.isStatic [
+    "--disable-flto"
   ];
 
   installFlags = [ "configfile=\${out}/etc/unbound/unbound.conf" ];