Now that the family and group are completely private to netlink_generic.c,
provide a simple and robust KPI, that would require very simple guarantees
from both KPI and the module:
- Strings are used only for family and group registration, that return ID: uint16_t genl_register_family(const char *name, ... uint32_t genl_register_group(uint16_t family, const char *name, ...
- Once created families and groups are guaranteed to not disappear and be addressable by their ID.
- All subsequent calls, including deregistration shall use ID.