pata_hpt3x2n: always stretch UltraDMA timing

The UltraDMA Tss timing must be stretched with ATA clock of 66 MHz, but the
driver only does this when PCI clock is 66 MHz, whereas it always programs
DPLL clock (which is used as the ATA clock) to 66 MHz.

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: <stable@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>