Fixes following errors:
Running test test-util-sockets
ERROR test-util-sockets - missing test plan

# Start of name tests
**
ERROR:../tests/test-util-sockets.c:93:test_socket_fd_pass_name_good: assertion failed (fd != -1): (-1 != -1)
Bail out! ERROR:../tests/test-util-sockets.c:93:test_socket_fd_pass_name_good: assertion failed (fd != -1): (-1 != -1)

First should call to qemu_init_main_loop before socket_init,
then on win32 doesn't support for SOCKET_ADDRESS_TYPE_FD socket type

Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200915121318.247-21-luoyonggang@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>