Don't set affinity if XDP is not in use

[alessandrod]

This fixes the validator not starting on macos, oops

[brooksprumo]

Built this branch on my macbook and confirmed I could run the validator successfully. Thanks!

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 9 lines in your changes missing coverage. Please review.

Project coverage is 82.8%. Comparing base (cbd3eb5) to head (7d719d0).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #6618   +/-   ##
=======================================
  Coverage    82.8%    82.8%           
=======================================
  Files         849      849           
  Lines      379357   379358    +1     
=======================================
+ Hits       314270   314306   +36     
+ Misses      65087    65052   -35     

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[mergify]

Backports to the beta branch are to be avoided unless absolutely necessary for fixing bugs, security issues, and perf regressions. Changes intended for backport should be structured such that a minimum effective diff can be committed separately from any refactoring, plumbing, cleanup, etc that are not strictly necessary to achieve the goal. Any of the latter should go only into master and ride the normal stabilization schedule. Exceptions include CI/metrics changes, CLI improvements and documentation updates on a case by case basis.