ideviceinstaller: fix build

The package ideviceinstaller fails to build, because it uses the
deprecated function zip_get_num_entries. This commit allows the usage of
deprecated functions to fix the build.

pkgs/tools/misc/ideviceinstaller/default.nix

@@ -30,6 +30,11 @@ stdenv.mkDerivation rec {
     libzip
   ];
 
+  # the package uses zip_get_num_entries, which is deprecated
+  env.NIX_CFLAGS_COMPILE = toString [
+    "-Wno-error=deprecated-declarations"
+  ];
+
   preAutoreconf = ''
     export RELEASE_VERSION=${version}
   '';