Remove CNI-specific conditional logic and update comments throughout
the libpod networking code:
- Simplified DNS configuration logic in container_internal_common.go
to always use netavark behavior (removed backend checks)
- Removed CNI-specific iptables chain error regex pattern
- Updated all comments referencing 'CNI' to use 'netavark' or
'network backend'
- Renamed variable 'cniNet' to 'netInfo' for clarity
- Updated field and type documentation to remove CNI references
All networking code now assumes netavark as the sole backend.
Signed-off-by: Lokesh Mandvekar <lsm5@redhat.com>
454167efa9