[FEA]: Deprecate and potentially remove CUB macros

[fbusato]

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Area

CUB

Is your feature request related to a problem? Please describe.

CUB still uses macros to define constant values, e.g. CUB_WARP_THREADS(0). This is widely considered a bad practice and bug-prone. Now with C++17 we have the opportunity to replace them with inline constexpr variables.

Describe the solution you'd like

Replace CUB macros used as constants with inline constexpr variables.
My preferred solution would be to remove the original macros. On the other hand, this is considered a breaking change, even though I don't expect users to directly adopt CUB macros in their code.

Describe alternatives you've considered

Replace and deprecate CUB macros

Additional context

No response