fix gfortran compiler detection (issue 305)
fix gfortran compiler detection (issue 305)

There was a typo in the check for the compiled fortran binary that made the check fail every time.

sourceryinstitute/opencoarrays,zbeekman/opencoarrays,jerryd/opencoarrays,jerryd/opencoarrays,sourceryinstitute/opencoarrays,zbeekman/opencoarrays,zbeekman/opencoarrays,jerryd/opencoarrays,sourceryinstitute/opencoarrays