Add gelu fuse ops

[MoisesHer]

Description

This PR adds into elementwise fused-operators LeakyReLU:gelu

Checklist

Essentials

Please feel free to remove inapplicable items for your PR.

• Changes are complete (i.e. I finished coding on this PR)
• All changes have test coverage:
• Unit tests are added for small changes to verify correctness (e.g. adding a new operator)
• Code is well-documented:
• To the best of my knowledge, examples are either not affected by this change, or have been fixed to be compatible with this change

Changes

• In pointwise fusion pass, set as fusion-compatible both LeakyReLU and _backward_LeakyReLU if activation type is in the provided list (only "gelu" for now)
• In the fused-ops code generator, include functions for LeakyReLU:gelu and _backward_LeakyReLU:gelu (they are equivalent to mshadow_op.h version)
• Included test into tests/python/gpu/test_fusion.py

Comments

[mxnet-bot]

Hey @MoisesHer , Thanks for submitting the PR
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[MoisesHer]

@mxnet-bot run ci [centos-gpu, unix-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [unix-gpu, centos-gpu]