nimble/host: Make preempt code multi advertising aware
nimble/host: Make preempt code multi advertising aware

X-Original-Commit: ccf66e5fa3aacdce749b6cfdf23930c1b4e5fd0f

apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble