Revert "[NDISC]: Fix race in generic address resolution"

This reverts commit 69cc64d8

.

It causes recursive locking in IPV6 because unlike other
neighbour layer clients, it even needs neighbour cache
entries to send neighbour soliciation messages :-(

We'll have to find another way to fix this race.

Signed-off-by: David S. Miller <davem@davemloft.net>