net/mlx5: fw reset: Skip device ID check if PCI link up failed

In case where after reset the PCI link is not ready within timeout, skip
reading device ID as if there is no PCI link up we can't have FW
response to pci config cycles either.

This also fixes err value not used and overwritten in such flow.

Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Shay Drory <shayd@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>