[io] Remove unnecessary local in RIoUring::IsAvailable
[io] Remove unnecessary local in RIoUring::IsAvailable

Co-authored-by: Axel Naumann <cb9efc8f9015dd95c88a8e735ee07ab4f1027cd2@cern.ch>
karies/root,karies/root,root-mirror/root,olifre/root,root-mirror/root,root-mirror/root,olifre/root,karies/root,karies/root,karies/root,karies/root,root-mirror/root,root-mirror/root,olifre/root,root-mirror/root,root-mirror/root,karies/root,olifre/root,olifre/root,olifre/root,karies/root,karies/root,olifre/root,karies/root,root-mirror/root,olifre/root,root-mirror/root,root-mirror/root,olifre/root,olifre/root,root-mirror/root,karies/root,olifre/root