fizz: Add missing documentation for setPreferIoUringSocket
fizz: Add missing documentation for setPreferIoUringSocket

Summary: As titled

Reviewed By: dmm-fb

Differential Revision: D40446472

fbshipit-source-id: b74b740706411dbb4607c0fb305703dbd7647ba4

facebook/wangle,facebook/wangle,facebook/wangle