From: Christian Schmidt <schmidt@digadd.de>

The serial_pci driver tries to guess serial ports on unknown devices
based on the PCI class (modem or serial). On certain softmodems (AC'97
modems) this can lead to the recognition of non-existing serial ports.

This patch adds a blacklist of PCI IDs that are to be ignored by the driver.

The patch applies against both 2.6.21.5 and 2.6.22-rc7.

Signed-off-by: Christian Schmidt <schmidt@digadd.de>