s390/qeth: fix retrieval of vipa and proxy-arp addresses

qeth devices in layer3 mode need a separate handling of vipa and proxy-arp
addresses. vipa and proxy-arp addresses processed by qeth can be read from
userspace. Introduced with commit 5f78e29c ("qeth: optimize IP handling
in rx_mode callback") the retrieval of vipa and proxy-arp addresses is
broken, if more than one vipa or proxy-arp address are set.

The qeth code used local variable "int i" for 2 different purposes. This
patch now spends 2 separate local variables of type "int".
While touching these functions hash_for_each_safe() is converted to
hash_for_each(), since there is no removal of hash entries.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Reference-ID: RQM 3524
Signed-off-by: David S. Miller <davem@davemloft.net>