Minor bugfix to make gpsim/matlab/demBarenco1.m run again.
Minor bugfix to make gpsim/matlab/demBarenco1.m run again.

TianpeiLuke/GPmat,SheffieldML/GPmat,TianpeiLuke/GPmat,SheffieldML/GPmat,TianpeiLuke/GPmat,SheffieldML/GPmat,TianpeiLuke/GPmat,SheffieldML/GPmat,TianpeiLuke/GPmat,SheffieldML/GPmat,TianpeiLuke/GPmat,SheffieldML/GPmat