fix zonespanlist() function on distributed index

[MBoldyrev]

When searching on a distributed index containing multiple local indices, and the conditions for reusing sorter are met, the sorter is created and stored at line searchd.cpp:8257:
pLocalSorter = sphCreateQueue ( tQueueSettings );
Then the local variable tQueueSettings leaves the 'if' block and disappears, together with its m_uPackedFactorFlags member, whose value was not stored anywhere. This leads to CSphQuery::m_bZSlist being false regardless zonespanlist() function presence in the query. As a result, garbage or crashes take place of the expected zone lists.