fdo#86687 Avoid deadlock updating progress bar

Change-Id: I13f93372fedc67bfd25d36a5bee10a004fe9f8f6
Reviewed-on: https://gerrit.libreoffice.org/13147Reviewed-by: Michael Meeks <michael.meeks@collabora.com>
Tested-by: Michael Meeks <michael.meeks@collabora.com>

sc/source/filter/excel/xetable.cxx

@@ -2087,9 +2087,12 @@ void XclExpRowBuffer::Finalize( XclExpDefaultRowData& rDefRowData, const ScfUInt
         for ( itr = itrBeg; itr != itrEnd; ++itr, ++nIdx )
             pTasks[ nIdx % nThreads ]->push_back( itr->second.get() );
 
-        for ( size_t i = 0; i < nThreads; i++ )
+        for ( size_t i = 1; i < nThreads; i++ )
             rPool.pushTask( pTasks[ i ] );
 
+        // Progress bar updates must be synchronous to avoid deadlock
+        pTasks[0]->doWork();
+
         rPool.waitUntilEmpty();
     }