qeth: synchronize configuration interface

Synchronize access to the drivers configuration interface.
Also do not allow configuration changes during online/offline
transition.

Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc drivers/s390/net/qeth_core.h
Simple merge

diff --cc drivers/s390/net/qeth_core_main.c
Simple merge

diff --cc drivers/s390/net/qeth_core_sys.c
Simple merge

diff --cc drivers/s390/net/qeth_l2_main.c
Simple merge

diff --cc drivers/s390/net/qeth_l3_main.c
Simple merge

diff --cc drivers/s390/net/qeth_l3_sys.c
Simple merge