tipc: Eliminate checks for empty zone list during name translation

Gets rid of a pair of checks to see if a name sequence entry in
TIPC's name table has an empty zone list. These checks are pointless
since the zone list can never be empty (i.e. as soon as the list
becomes empty the associated name sequence entry is deleted).

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>