#2698 cmpi-base: system name might have empty domainname

[Klaus Kämpf]

OSBase_Common.c:_init_system_name() takes insufficient caution to create a fully-qualified domain name for the system. If /bin/dnsdomainname returns nothing, no further checks are done.

Attached is a patch to fall back to /bin/domainname if /bin/dnsdomainname returns error or an empty string.

[Dave Heller]

I noticed that on redhat distros the domainname command might return "(none)", so I added a simple check for that.

Thanks again, Klaus!

Committed to git master for cmpi-base 1.6.3 as [3f41cf]