[libc] Fix benchmarks build.

Reviewers: gchatelet, echristo

Subscribers: mgorny, tschuett, libc-commits

Tags: #libc-project

Differential Revision: https://reviews.llvm.org/D79040

GitOrigin-RevId: 1852af16a1c52e5d61e30a43ed74a446514152fc
3 files changed