add support for:

  4348:5523 WinChipHead USB->RS 232 adapter with Prolifec PL 2303 chipset

[ mingo@elte.hu: merged it and nursed it upstream ]

Cc: stable <stable@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>