This removes PKG_VERSION and PKG_RELEASE from most Makefiles, as the
value was never useful for Gluon packages; instead, PKG_VERSION is set
to 1 in gluon.mk.
It also removes two other weird definitions:
- gluon-iptables-clamp-mss-to-pmtu replicating the old PKG_VERSION logic
from gluon-core, but without the fixed PKG_BUILD_DIR to prevent
unnessary rebuilds
- gluon-hoodselector set GLUON_VERSION=3
macvlan interfaces never directly exchange traffic with the underlying
interface, but only with other hosts behind the interface. In consequence,
router advertisements from the uradvd running on br-client could never
reach local-node, preventing it from getting an IPv6 address without RAs
from an external radvd. Fix this be replacing the macvlan interface with
a veth pair (with the peer interface in br-client).
As a side effect, this saves about 5KB of flash, as the veth module is
simpler than macvlan.
