mass rewrite of find parameters to cross-platform style

Fixes #9044, close #9667. Thanks to @taku0 for suggesting this solution.
Now we have no modes starting with `/` or `+`.

Rewrite the `-perm` parameters of find:
 - completely safe: rewrite `/0100` and `+100` to `-0100`,
 - slightly semantics-changing: rewrite `+111` to `-0100`.
I cross-verified the `find` manual pages for Linux, Darwin, FreeBSD.

pkgs/tools/graphics/quirc/default.nix

@@ -26,7 +26,7 @@ stdenv.mkDerivation {
   '';
   preInstall = ''
     mkdir -p "$out"/{bin,lib,include}
-    find . -maxdepth 1 -type f -perm +111 -exec cp '{}' "$out"/bin ';'
+    find . -maxdepth 1 -type f -perm -0100 -exec cp '{}' "$out"/bin ';'
   '';
   makeFlags = "PREFIX=$(out)";
   meta = {