pgioperf: Compile with -lrt

Signed-off-by: Mel Gorman <mgorman@suse.de>
pgioperf: Adjust temporary file handling

Signed-off-by: Mel Gorman <mgorman@suse.de>
pgioperf: Add reporting scripts

Signed-off-by: Mel Gorman <mgorman@suse.de>