We haven't exposed so far any tunable parameters for magmablas. Only
for the higher level algorithms we have exposed the blocking size.
Note that in general we use magmablas as complementary to cublas where
tuning is done for specific needs of various magma algorithms. Ideally,
we would like to see our improvements added to CUBLAS, e.g., as in
the case of the new MAGMA BLAS gemms for Fermi