trusty: improve identification of the kernel build_id

pick the oldest LKGB among the 3 kernel build targets:
- kernel_aarch64
- kernel_virt_aarch64
- trusty_aarch64

in the hope that the oldest LKGB holds a successful
completed build for the 3 targets needed for booting
the Trusty QEMU testbench.

Bug: 421296244
Test: acloud-dev create --avd-type trusty --branch=git_main \
      --build-target=qemu_trusty_arm64-trunk_staging-userdebug \
      --kernel-branch=aosp_kernel-common-android16-6.12
Change-Id: I3b6c7c8943a433f08bf629e638628632303b877e
1 file changed