[automerger skipped] [Thread] add Android.bp for Thread flags am: a59a6e304b -s ours am: 4135786d7a -s ours

am skip reason: Merged-In I88c993680976d2e10d672bfdbf45119f2db13868 with SHA-1 da8fac1edb is already in history

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2900567

Change-Id: Ieb9269fe5e97d851dd6e9a7b6fab4b0ad4624532
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>