Don't save PCI state when PCI error is detected in mlx5core.

When a PCI error is detected the PCI state could be corrupt, don't
save it in that flow. Save the state after initialization. After
restoring the PCI state during slot reset save it again, restoring
the state destroys the previously saved state info.

Submitted by: slavash@
MFC after: 1 week
Sponsored by: Mellanox Technologies