Open-sourcing Habana back end for Glow

What this post added

Introduced an experimental back end for the Glow compiler to target Habana's hardware accelerators. This is the first vendor-specific accelerator back end for Glow, enabling partners to design and optimize new silicon products for ML and strengthening the ecosystem for accelerating neural network ML workloads at production scale. The back end targets Habana's inference accelerator cards and is intended to improve ML performance on supported hardware, with applications in computer vision, recommendation, personalization, and natural language processing.