Check Initialization of prng with same_rnd_numbers (Defect #471)
To get the same rnd numbers devicetype independent, the size of the prng buffer has to be set to a uniform value.
Currently, this is one.
This gave the same rnd numbers in test gm_gaussian_3, f1b4ab64.
Apperently, this is not taken into account sufficiently in the initialization of the seeds.
Also, I noticed that with the present code, on a CPU the prng does not work when the buffer_size exceeds some value, ie vol4d/2. This might also have to do with the init.