Suppress -Wformat am: df93b4f377

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/zopfli/+/38786223

Change-Id: I1e7d20c410d6a1a023f3081f8fc226212848660f
Signed-off-by: Automerger Merge Worker <[email protected]>