C11 has been the platform (and compiler) default for a while now. am: a9963b538c am: e10ea8f194 am: 6a5d255168 am: 2e4d6eb116 am: 23392ce8f7 am: 7ec137f798

Original change: https://android-review.googlesource.com/c/platform/external/mtools/+/2628331

Change-Id: Ibefbc23764086285fbe3fe0cd25918b1c3a166df
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>