sfc: falcon: Search VPD with pci_vpd_find_ro_info_keyword()

This is the same as 37838aa4 "sfc: Search VPD with
pci_vpd_find_ro_info_keyword()", just for the falcon chip version.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>