net: rbridge: fix TRILL ethernet addresses

Fix TRILL addresses defines according to RFC6325

Signed-off-by: François Cachereul <f.cachereul@alphalink.fr>
Signed-off-by: William Dauchy <william@gandi.net>
Signed-off-by: Ahmed Amamou <ahmed@gandi.net>
net: rbridge: code cleaning and trivial fix

The first one is trivial and for the second the pointer should be tested
before being dereferenced

Signed-off-by: François Cachereul <f.cachereul@alphalink.fr>
Signed-off-by: William Dauchy <william@gandi.net>
Signed-off-by: Ahmed Amamou <ahmed@gandi.net>
net: rbridge: Add layer 2 IS-IS Ethertype

Signed-off-by: François Cachereul <f.cachereul@alphalink.fr>
Signed-off-by: William Dauchy <william@gandi.net>
Signed-off-by: Ahmed Amamou <ahmed@gandi.net>