[partition] Rename slots, to avoid recursion

- see also https://github.com/calamares/calamares/issues/880
- missed within 7ce52ecda7

src/modules/partition/jobs/SetPartitionFlagsJob.cpp

@@ -135,7 +135,7 @@ SetPartFlagsJob::exec()
     Report report ( nullptr );
     SetPartFlagsOperation op( *m_device, *partition(), m_flags );
     op.setStatus( Operation::StatusRunning );
-    connect( &op, &Operation::progress, this, &SetPartFlagsJob::progress );
+    connect( &op, &Operation::progress, this, &SetPartFlagsJob::iprogress );
 
     QString errorMessage = tr( "The installer failed to set flags on partition %1." )
                            .arg( m_partition->partitionPath() );