There are only three users which require it to be reentrant, the rest is
fine without. Instead, provide a reentrant format_host_r() for users
which need it.
Signed-off-by: Phil Sutter <phil@nwl.cc>
There have been several instances where response from kernel
has overrun the stack buffer from the caller. Avoid future problems
by passing a size argument.
Also drop the unused peer and group arguments to rtnl_talk.
