aten cpu and xnnpack to be compatible with arvr mode build (#87125)
Summary:
When building 3d photo sdk generator package in arvr/mode/mac and arvr/mode/mac-arm modes, we got several issues with aten cpu and xnnpack libraries.
The reason is that those packages are using platform-* properties (platform-deps, platform-srcs...) which are not compatible with arvr modes.
This diff fixes those issues by using `select` for non-platform properties when is_arvr_mode() is true, while keeping those platform ones for non-arvr modes.
Test Plan:
```
buck build //arvr/projects/compphoto/photo3d_sdk/unity/plugin:generator_plugin_shared arvr/mode/mac-arm/dev
buck build //arvr/projects/compphoto/photo3d_sdk/unity/plugin:generator_plugin_shared arvr/mode/mac-arm/opt
buck build //arvr/projects/compphoto/photo3d_sdk/unity/plugin:generator_plugin_shared arvr/mode/mac/dev
buck build //arvr/projects/compphoto/photo3d_sdk/unity/plugin:generator_plugin_shared arvr/mode/mac/opt
```
and sandcastle builds
Differential Revision: D40028669
Pull Request resolved: https://github.com/pytorch/pytorch/pull/87125
Approved by: https://github.com/kimishpatel
