Added necessary synchronization to register.f90 test to prevent non-deterministic test failure.
Added necessary synchronization to register.f90 test to prevent non-deterministic test failure.

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