kernel: Use pahole from Google prebuilts

This fixes the following warnings:

  13:04:54 Disallowed PATH tool "pahole" used: []string{"pahole", "--version"}
  13:04:54 See https://android.googlesource.com/platform/build/+/master/Changes.md#PATH_Tools for more information.
  "pahole" is not allowed to be used. See https://android.googlesource.com/platform/build/+/master/Changes.md#PATH_Tools for more information.
  /home/bgcngm/android/lineage/kernel/oneplus/sm8550/scripts/pahole-flags.sh: 12: [: Illegal number:
  /home/bgcngm/android/lineage/kernel/oneplus/sm8550/scripts/pahole-flags.sh: 16: [: Illegal number:
  /home/bgcngm/android/lineage/kernel/oneplus/sm8550/scripts/pahole-flags.sh: 20: [: Illegal number:

Change-Id: Ice2a3753301a7b7782037fd35544e2831b258650