move const defs of DeviceType to DeviceType.h (#19185)
Summary:
Stack:
:black_circle: **#19185 [c10][core][ez] move const defs of DeviceType to DeviceType.h** [:yellow_heart:](https://our.intern.facebook.com/intern/diff/D14909415/)
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Pull Request resolved: https://github.com/pytorch/pytorch/pull/19185
Differential Revision: D14909415
Pulled By: jerryzh168
fbshipit-source-id: 876cf999424d8394f5ff20e6750133a4e43466d4
