Remove unnecessary null pointer checks

[elfring]

An extra null pointer check is not needed in functions like the following.

• GlfUVTextureStorageData
• HdMeshTopology::SetQuadInfo

[amooty]

Filed as internal issue #135159.

[superfunc]

Note this code has been cleaned up since and can be closed: https:/PixarAnimationStudios/USD/blob/022f7ef54ff8ce15120f34e61e078c1daf471153/pxr/imaging/lib/hdSt/meshTopology.cpp#L83-87

[elfring]

There are further update candidates to consider, aren't there?

[superfunc]

Looks like I was wrong; I hadn't realized this was pointing to a more general problem and not those specific callouts, my apologies.

[elfring]

I am just curious if all possible improvements were integrated into this software for the reported search pattern.

[elfring]

Would you like to take another look also at any included software libraries?

[elfring]

How will the software evolution be continued around a class like “GlfUVTextureStorageData”?

[elfring]

How do you think about to use a development tool like “clang-tidy” for corresponding source code adjustments?