Update kernel to builds 8747247 am: b92068fae0 am: 9ce2252b48 am: d7344670fe

Original change: https://googleplex-android-review.googlesource.com/c/kernel/prebuilts/5.15/arm64/+/19007989

Change-Id: I4ca6fc323a87aa1a34ce4fa676785ed27f93e73b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>