Use control.xml to set DNS.dhcp_hostname (bnc#870896)

In order to completely close the bug, changes in control.xml for both SLED and
SLES are needed.
Changelog and version updates
Fixed initialization of LLADDR. HWAddr replaced by OSAHWAddr. bnc#889287

From linuxrc's help: Manual MAC address setting for Layer 2-enabled OSA
devices. Note that this is distinct from HWAddr, which contains the
default MAC address as detected by linuxrc.
Fixed testsuite
Updated changelog
Merge pull request #262 from mchf/SLE-12-GA

Ported last fixes into SLE-12 branch