[metal] Add reflection_pad2d for metal (#58263)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/58263
Add the `reflection_pad2d` op in preparation for newer xirp models.
Test Plan:
Test on device:
```
arc focus2 pp-ios
```
Test on mac
```
buck test pp-macos
```
Reviewed By: xta0
Differential Revision: D27047892
fbshipit-source-id: 815856e19e4885c352f5d7174866480db7641cdf
