qtests: avoid printing comments before g_test_init()

qtests: avoid printing comments before g_test_init()

The TAP protocol version line must be the first thing printed on
stdout. The migration test failed that requirement in certain
scenarios:

  # Skipping test: Userfault not available (builtdtime)
  TAP version 13
  # random seed: R02Sc120c807f11053eb90bfea845ba1e368
  1..32
  # Start of x86_64 tests
  # Start of migration tests
  ....

The TAP version is printed by g_test_init(), so we need to make
sure that any methods which print are run after that.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230317170553.592707-1-berrange@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>