Revert "PCI: Use preserve_config in place of pci_flags"

This reverts commit c1a1393f which is
commit 7246a452 upstream.

This patch causes a regression in cuttlefish/crossvm boot on arm64.

The patch was part of a series that when applied will not cause a regression
but this patch was backported to the 5.15 branch by itself.

The other patches do not apply cleanly to the 5.15 branch.

Signed-off-by: Terry Tritton <terry.tritton@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>