Remove -Wall from cflags. am: 5b448cde8f am: aba9ca572f am: 33be3f2219

Original change: https://android-review.googlesource.com/c/platform/system/libziparchive/+/2794926

Change-Id: Iba1f86ddfe73562d99a39a06490e3045ab283c68
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>