libata: fix assigned IRQ reporting

host->irq and host->irq2 should be set before ata_host_register() for
IRQ reporting to work.  Move up host->irq assignment in
ata_host_activate() and add it to ata_pci_init_one() native path and
pata_cs5520.

The port info printing in ata_host_register() doesn't fit all the
different controllers.  It should probably be moved out to LLDs with
some helpers in the future.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>