lock_guard: remove explicit template

src/connectionmanager.cpp

src/fileutils.cpp

src/ice_transport.cpp

src/multiplexed_socket.cpp

src/peer_connection.cpp

src/security/certstore.cpp

src/security/diffie-hellman.cpp

src/security/threadloop.h

src/security/tls_session.cpp

src/transport/peer_channel.h

src/turn/turn_cache.cpp

src/turn/turn_transport.cpp

src/upnp/protocol/igd.h

src/upnp/protocol/mapping.cpp

src/upnp/protocol/natpmp/nat_pmp.cpp

src/upnp/protocol/pupnp/pupnp.cpp

src/upnp/protocol/pupnp/upnp_igd.h

src/upnp/upnp_context.cpp

src/upnp/upnp_control.cpp

tests/connectionManager.cpp