dispatch max_pools with no indices, expose max_pools to torch namespace (#19449)
Summary:
in functional interfaces we do boolean dispatch, but all to max_pool\*d_with_indices. This change it to emit max_pool\*d op instead when it's not necessary to expose with_indices ops to different backends (for jit).
It also bind max_pool\*d to the torch namespace, which is the same behavior with avg_pool\*d
Pull Request resolved: https://github.com/pytorch/pytorch/pull/19449
Differential Revision: D15016839
Pulled By: wanchaol
fbshipit-source-id: f77cd5f0bcd6d8534c1296d89b061023a8288a2c
