Remove the test_gets_num_clients test from the C unit tests

This test was causing problems by using dummy pointers to simulate
connections.  When calling the cleanup code, these pointers were
thought to be real, and the code attemtped to clean up threads
referenced by those pointers, causing a segfault.

I've reimplemented the test in the ruby acceptance suite.

tests/acceptance/test_serve_mode.rb

@@ -209,12 +209,15 @@ class TestServeMode < Test::Unit::TestCase
   end
 
   def test_status_returns_correct_client_count
-    require 'pp'
+    @env.writefile1('0')
-    connect_to_server do |client|
+    @env.serve1
-      status = @env.status1
+    assert_equal('0', @env.status1['num_clients'])
-      assert_equal('1', status['num_clients'])
+    client = FlexNBD::FakeSource.new(@env.ip, @env.port1, 'Connecting to server failed')
-    end
+    assert_equal('1', @env.status1['num_clients'])
-    status = @env.status1
+    client2 = FlexNBD::FakeSource.new(@env.ip, @env.port1, 'Connecting to server failed')
-    assert_equal('0', status['num_clients'])
+    assert_equal('2', @env.status1['num_clients'])
+    client2.close
+    client.close
+    assert_equal('0', @env.status1['num_clients'])
   end
 end

tests/unit/check_status.c

@@ -105,25 +105,6 @@ START_TEST( test_gets_clients_allowed )
 }
 END_TEST
 
-START_TEST( test_gets_num_clients )
-{
-	struct server * server = mock_server();
-	struct status * status = status_create( server );
-
-	fail_if( status->num_clients != 0, "num_clients was wrong" );
-	status_destroy( status );
-
-	server->nbd_client[0].thread = 1;
-	server->nbd_client[1].thread = 1;
-	status = status_create( server );
-
-	fail_unless( status->num_clients == 2, "num_clients was wrong" );
-	status_destroy( status );
-	destroy_mock_server( server );
-
-}
-END_TEST
-
 START_TEST( test_gets_pid )
 {
 	struct server * server = mock_server();