remove a warning building a test
remove a warning building a test

With my compile switches (which are mostly derived from RedHat spec
file) I'm getting this warning:

stream-test.c: In function 'sock_fd_read':
stream-test.c:66:43: warning: dereferencing type-punned pointer will
break strict-aliasing rules [-Wstrict-aliasing]
             *fd = *((int *) CMSG_DATA(cmsg));
                                           ^

memcpy could decrease performance but as this is a test it's not
an issue.

Signed-off-by: Frediano Ziglio <55d48b080b2e443e395cde84d2c83b135a4ff48e@redhat.com>
Acked-by: Christophe Fergeau <05b95054a663c388a4e33d95828cb30f0370f8ef@redhat.com>

fgouget/spice,fgouget/spice,fgouget/spice,fgouget/spice