8b2c733 clarify abortrescan rpc use (Gregory Sanders)
Pull request description:
`-rescan` during startup doesn't apply since RPC has not warmed up by that point
Tree-SHA512: 0b6738ed9429ca41edbfa23bb3e2da23bb16fed9e55c1803ab140b2efc49ef3295bb8b7eeb8c24df94204c5b3fb25d0d57cbc8d1be11856a5763c9fde71bceba
Backport of Core PR11753
https://github.com/bitcoin/bitcoin/pull/11753/