[NET]: Process include/linux/if_{addr,link}.h with unifdef
After commit d3dcc077bf88806201093f86325ec656e4dbfbce,
include/linux/if_{addr,link}.h should be processed with unifdef.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>