faft: Remove port arg from disconnect_ssh_tunnel() and usages

Part of the android deprecation effort.

The method's "port" argument is no longer useful since
only ADBHost/android used it.

BUG=b:138222680
TEST=ran firmware_FAFTRPC.all

Change-Id: I42714703c09b6dc12c655b8f0de2d666bc5a3a14
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/autotest/+/1872472
Commit-Queue: Oleg Loskutoff <[email protected]>
Tested-by: Oleg Loskutoff <[email protected]>
Reviewed-by: Wai-Hong Tam <[email protected]>
diff --git a/server/hosts/rpc_server_tracker.py b/server/hosts/rpc_server_tracker.py
index feb7890..60f9bfa 100644
--- a/server/hosts/rpc_server_tracker.py
+++ b/server/hosts/rpc_server_tracker.py
@@ -295,7 +295,7 @@
                     raise error.TestError('Failed to shutdown RPC server %s' %
                                           remote_name)
 
-        self._host.disconnect_ssh_tunnel(tunnel_proc, port)
+        self._host.disconnect_ssh_tunnel(tunnel_proc)
         del self._rpc_proxy_map[port]