Force complex64 in ns_mmq_2site_mq.
This solves all systemtests.
Forcing to be complex64, does not seems like a long standing solution, since complex128 is possible.
Task #7807 (https://gna.org/task/index.php?7807): Speed-up of dispersion models for Clustered analysis.
Authored by: tlinnet 2014-06-20
Parent: [r24199]
Child: [r24201]
