Some numpy_usm_shared registrations are failing eval.

[DrTodd13]

In numpy_usm_shared where we iterate through functions and register them with Numba, we do an eval of the function name and for now some of those are failing. I added try/except around the eval so we can skip ones that fail eval for now but we need to fix this soon.

[diptorupd]

Closing as numpy_usm_shared is slotted for removal in 0.20 (Refer #841)