Match cache size between puffdiff and lz4diff am: ea4ca42744 am: 80c79779cc

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/2850109

Change-Id: I3d66192ecdfc87bad0d933c870280290cfc7f5b7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>