[HostsQueryOption] Add a missing copy constructor

This commit fixes the following compile time warning:

testArmBase.cc:549:38: warning: no viable constructor copying parameter of type 'HostsQueryOption'; C++98 requires a copy constructor when binding a reference to a temporary
      [-Wbind-to-temporary-copy]
        dbMonitoring.getHostInfoList(hosts, HostsQueryOption(USER_ID_SYSTEM));
Merge pull request #843 from project-hatohol/add-missing-copy-constructor

[HostsQueryOption] Add a missing copy constructor