check-dist: don't try to open /dev/stderr
check-dist: don't try to open /dev/stderr

Running this script could fail because /dev/stderr could be a symlink to
a socket or a file that we don't have permission to open().  In the case
of running it under toolbox, for example, it's a link to a pty which is
inaccessible to the current user.

In the case that the check fails, just run the command again to get the
debugging output.

garrett/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,mvollmer/cockpit,mvollmer/cockpit,garrett/cockpit,martinpitt/cockpit,cockpit-project/cockpit,mvollmer/cockpit,martinpitt/cockpit,garrett/cockpit,mvollmer/cockpit,martinpitt/cockpit,garrett/cockpit,martinpitt/cockpit,garrett/cockpit,cockpit-project/cockpit,martinpitt/cockpit,mvollmer/cockpit