Fix the following failed tests on NV,
hipCGMultiGridGroupType
hipCGMultiGridGroupTypeViaBaseType
hipCGMultiGridGroupTypeViaPublicApi
1. Fix wrong logic in kernel for both AMD and NV.
2. Remove unnecessary hipDeviceSynchronize().
3. In hipCGMultiGridGroupTypeViaBaseType.cpp, change
multi_grid_group as thread_group which is originally expected.
4. hipFree(syncResultD) is fixed as hipHostFree(syncResultD)
5. Optimize some host codes.
Change-Id: I3fe6dac35a7b14bab12adf397b7885df83d28059
[ROCm/hip commit: c57e0f8fe5]