ata: libata: simplify qc_fill_rtf port operation interface

The boolean return value of the qc_fill_rtf operation is used nowhere.
Simplify this operation interface by making it a void function. All
drivers defining this operation are also updated.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>