update_kernel_afdo: Remove 3.18

Remove 3.18 from the kernel AFDO update.

BUG=b:199787442
TEST=./update_kernel_afdo

Change-Id: I343d2048fb6bbd9c3c9f37bdfe64526a91c68220
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/3162669
Tested-by: Denis Nikitin <denik@chromium.org>
Reviewed-by: Bob Haarman <inglorion@chromium.org>
Commit-Queue: Denis Nikitin <denik@chromium.org>
1 file changed