pxrConfig.cmake - don't bake in absolute paths for MaterialX/Imath/"work"

[pmolodo]

Description of Change(s)

Avoids baking absolute paths for MaterialX/Imath/"work".

The baking of the absolute path locations for various CMake dependencies into pxrConfig.cmake makes it less portable.

Link to proposal (if applicable)

https://github.com/aousd/build-ig-initiatives/issues/15

Fixes Issue(s)

• absolute paths getting baked into pxrConfig.cmake

Checklist

• I have created this PR based on the dev branch

• I have followed the coding conventions

• [] I have added unit tests that exercise this functionality (Reference:
  testing guidelines)

• [] I have verified that all unit tests pass with the proposed changes

• I have submitted a signed Contributor License Agreement (Reference:
  Contributor License Agreement instructions)

[sunyab]

@pmolodo Hey Paul, I'm unable to access the aousd/build-ig-initiatives page you linked to -- is that meant to be public?

[jesschimein]

Filed as internal issue #USD-11708

(This is an automated message. See here for more information.)

[dlarsson-adobe]

@pmolodo Hey Paul, I'm unable to access the aousd/build-ig-initiatives page you linked to -- is that meant to be public?

It's currently not public (so it might not be good to reference it on a public repo). You can access it through aousd git access. Reach out on slack if you need help with this

[dlarsson-adobe]

This looks good to me

[pmolodo]

@pmolodo Hey Paul, I'm unable to access the aousd/build-ig-initiatives page you linked to -- is that meant to be public?

Hmm... no, it's not public, but you should be a member of build-ig-initiatives, and have access.

Longer term, I'll bring it up in the Build Interest Group - ie, if we want to make it public, and if not, how we can reference initiatives in public places, like OpenUSD.