It's unclear whether it has to be, but there are a lot of patches floating around
on the net that indicate that Coverty requires this, and the SIOCGIFADDR micro-howto
also NUL-terminates the string.

So who is Qt to differ?

Change-Id: I1aa5a2de47a58b1d9b73556d5a6ddc48b2c40ce3
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>