pci: Add PCI LRDT tag size and section size

This patch adds a preprocessor constant to describe the PCI VPD large
resource data type tag size and an inline function to extract the large
resource section size from the large resource data type tag.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: David S. Miller <davem@davemloft.net>