serial: add pci ids for PA Semi PWRficient onchip uarts

Add PCI IDs for the onchip UARTs on PA Semi PWRficient.

Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>