PCI: faraday: Make struct faraday_pci_variant static

This was generated from 0-day builder.

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
[lorenzo.pieralisi@arm.com: reworked/split patch]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>