In some cases we have alternative configuration options that supply the
same functionality, e.g CONFIG_NET and CONFIG_NET_LWIP.

Allow to specify all of them as arguments for buildconfigspec() and execute
the text if any of these is fulfilled, e.g.

    @pytest.mark.buildconfigspec('net', 'net_lwip')

Update the documentation.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Acked-by: Jerome Forissier <jerome.forissier@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

Begin the work of documenting all of our pytests. To do this, we should
have a directory under develop for it as there will be a large number of
new files. As the current document is referenced externally in a number
of locations, add the sphinx_reredirects module so that we can redirect
from the old location to the new.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>