test-char: fix random socket test failure

test-char: fix random socket test failure

Peter reported a test failure on FreeBSD with the new reconnect test:

MALLOC_PERTURB_=${MALLOC_PERTURB_:-$(( ${RANDOM:-0} % 255 + 1))}
gtester -k --verbose -m=quick tests/test-char
TEST: tests/test-char... (pid=16190)
  /char/null:                                                          OK
  /char/invalid:                                                       OK
  /char/ringbuf:                                                       OK
  /char/mux:                                                           OK
  /char/stdio:                                                         OK
  /char/pipe:                                                          OK
  /char/file:                                                          OK
  /char/file-fifo:                                                     OK
  /char/udp:                                                           OK
  /char/serial:                                                        OK
  /char/hotswap:                                                       OK
  /char/socket/basic:                                                  OK
  /char/socket/reconnect:                                              FAIL
GTester: last random seed: R02S521380d9c12f1dac3ad1763bf5665c27
(pid=16367)
  /char/socket/fdpass:                                                 OK
FAIL: tests/test-char
**
ERROR:tests/test-char.c:353:char_socket_test_common: assertion failed:
(object_property_get_bool(OBJECT(chr_client), "connected",
&error_abort))

It turns out that the socket test code checks both server and client
connection states, but doesn't wait for both.

Wait for the client side as well.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20180823143125.16767-5-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>