Fix editing of tables without rowid

This fixes some severe bugs in the Browse Data tab with editing and
deleting rows in WITHOUT ROWID tables.

These were introduced in 02db68107a.

See issue #2582.

src/sqlitetablemodel.cpp

@@ -934,6 +934,9 @@ bool SqliteTableModel::dropMimeData(const QMimeData* data, Qt::DropAction, int r
 
 void SqliteTableModel::setPseudoPk(std::vector<std::string> pseudoPk)
 {
+    if(!m_table_of_query->isView())
+        return;
+
     if(pseudoPk.empty())
         pseudoPk.emplace_back("_rowid_");