Remove affordance for adding SSH keys

Instead these will be injected into system via mechanism in 'fx'.

Change-Id: I86869f2dc39d7853e6c589cd9b1abd27d2832780
diff --git a/fuchsia/developer-keys/BUILD.gn b/fuchsia/developer-keys/BUILD.gn
index a3a1dc0..469d006 100644
--- a/fuchsia/developer-keys/BUILD.gn
+++ b/fuchsia/developer-keys/BUILD.gn
@@ -2,38 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/package.gni")
-
-declare_args() {
-  # Additional SSH authorized_keys file to include in the build.
-  # For example:
-  #   extra_authorized_keys_file=\"$HOME/.ssh/id_rsa.pub\"
-  extra_authorized_keys_file = ""
-}
-
-package("developer-keys") {
-  deprecated_system_image = true
-
-  deps = [
-    ":all",
-  ]
-
-  resources = []
-
-  if (extra_authorized_keys_file != "") {
-    resources += [{
-      path = rebase_path(extra_authorized_keys_file)
-      dest = "ssh/authorized_keys"
-    }]
-  }
-}
-
-group("all") {
-  public_deps = [
-    ":ssh_config",
-  ]
-}
-
 keys_dir = "${root_build_dir}/ssh-keys"
 
 action("ssh_config") {