[Fuchsia] Bind Observatory to ipv4 any

BUILD.gn

 # Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 # This target will be built if no target is specified when invoking ninja.
 group("default") {
   if (defined(is_fuchsia) && (is_fuchsia || is_fuchsia_host)) {
     # Fuchsia has run_vm_tests marked testonly.
     testonly = true
   }
@@ skipping 249 matching lines @@
       ]
 
       script = "//packages/gn/make_bootfs.py"
       args = [
         "--manifest",
         rebase_path(input),
         "--output-file",
         rebase_path(output),
         "--build-id-map",
         rebase_path("$target_gen_dir/build_id_map"),
-        "--compress",
         "--pre-binaries",
         rebase_path(magenta_bootdata),
       ]
     }
   }
 }