Add rfkill.c/rfkill.h to be used for watching per-wiphy RFkill state.
It uses both /dev/rfkill and /sys because /dev/rfkill is the recommended
way of interfacing with rfkill but at the same time it doesn't provide
the information on mapping to wiphy IDs.
--interfaces (-i) tells iwd which interfaces to manage. If the option
is ommitted, all interfaces will be managed.
--nointerfaces (-I) tells iwd which interfaces to blacklist. If the
option is ommitted, no interfaces will be blacklisted.
knownnetworks.c/.h implements the KnownNetworks interface and loads the
known networks from storage on startup. The list of all the networks
including information on whether a network is known is managed in
network.c to avoid having two separate lists of network_info structures
and keeping them in sync. That turns out to be difficult because the
network.c list is sorted by connected_time and connected_time changes
can be triggered in both network.c or knownnetworks.c. Both can also
trigger a network_info to be removed completely.
Turn netdev watches into device watches. The intent is to refactor out
netdev specific details into its own class and move device specific
logic into device.c away from wiphy.c
It seems until now dbus.c would always connect to dbus-1 (unless
DBUS_SESSION_BUS_ADDRESS pointed at kdbus) and passing -K only made
iwd create a kdbus bus and not use it. Now use ell to actually use
kdbus instead of dbus-1 with -K. Don't use the src/kdbus.c functions
that duplicate ell functionality. As a side effect the connection
description and the bloom sizes are now the ell defaults.
