kernel: Add cos_patch_trailer_check repohook check. BUG=b/179054156 TEST=local testing RELEASE_NOTE=None Change-Id: I73dce2ecb790fb947d420f85e41b9c8bdc0d2007 Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/11877 Reviewed-by: Dexter Rivera <riverade@google.com> Tested-by: Vaibhav Rustagi <vaibhavrustagi@google.com>