update_kernel_afdo: Handle missing profiles

Skip arch/kver update if profiles are missing in the current and
previous milestone.

BUG=b:284158194
TEST=./update_kernel_afdo --noupload main

Change-Id: I8dc74e0a2f9fa3790b080c262773d76f7293307a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/4571164
Tested-by: Denis Nikitin <denik@chromium.org>
Reviewed-by: Ryan Beltran <ryanbeltran@chromium.org>
Commit-Queue: Denis Nikitin <denik@chromium.org>
1 file changed