net: correct check in dev_addr_del()

[ Upstream commit a652208e0b52c190e57f2a075ffb5e897fe31c3b ]

Check (ha->addr == dev->dev_addr) is always true because dev_addr_init()
sets this. Correct the check to behave properly on addr removal.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>