ACPI: thinkpad-acpi: store ThinkPad model information

Keep note of ThinkPad model, BIOS and EC firmware information, and log it
on startup.  Makes for far more readable code in places, too.

This patch also adds Lenovo's PCI ID to the pci ids table.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>