s2io: remove unused code

usr_addrs is never referenced outside the initial struct population
during open, thus making it unnecessary.  Remove it, the code that
references it, and the struct that it is the only user of.

Signed-off-by: Jon Mason <jon.mason@exar.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc drivers/net/s2io.c
Simple merge

diff --cc drivers/net/s2io.h
Simple merge