postgres: filter out null parameters in pg_file_settings view.
postgres: filter out null parameters in pg_file_settings view.

If some pg_parameters that cannot be changed without a restart
are removed from the postgresql.conf file the view will contain some
rows with null name and setting and the error field set to the cause.

So we have to filter out these or the Scan will fail.

siepkes/stolon,sgotti/stolon,smkingsoft/stolon,siepkes/stolon,sorintlab/stolon,smkingsoft/stolon,sgotti/stolon,sorintlab/stolon