Merge bitcoin/bitcoin#24513: CChainState -> Chainstate

00eeb31c76 scripted-diff: rename CChainState -> Chainstate (James O'Beirne)

Pull request description:

  Alright alright alright, I know: we hate refactors. We especially hate cosmetic refactors.

  Nobody knows better than I that changing broad swaths of code out from under our already-abused collaborators, only to send a cascade of rebase bankruptcies, is annoying at best and sadistic at worst. And for a rename! The indignation!

  But just for a second, imagine yourself. Programming `bitcoin/bitcoin`, on a sandy beach beneath a lapis lazuli sky. You go to type the name of what is probably the most commonly used data structure in the codebase, and you *only hit shift once*.

  What could you do in such a world? You could do anything. [The only limit is yourself.](https://zombo.com/)

  ---

  So maybe you like the idea of this patch but really don't want to deal with rebasing. You're in luck!

  Here're the commands that will bail you out of rebase bankruptcy:

  ```sh
  git rebase -i $(git merge-base HEAD master) \
    -x 'sed -i "s/CChainState/Chainstate/g" $(git ls-files | grep -E ".*\.(py|cpp|h)$") && git commit --amend --no-edit'
  # <commit changed?>
  git add -u && git rebase --continue
  ```

  ---

  ~~Anyway I'm not sure how serious I am about this, but I figured it was worth proposing.~~ I have decided I am very serious about this.

  Maybe we can have nice things every once in a while?

ACKs for top commit:
  MarcoFalke:
    cr ACK 00eeb31c76
  hebasto:
    ACK 00eeb31c76
  glozow:
    ACK 00eeb31c76, thanks for being the one to propose this
  w0xlt:
    ACK 00eeb31c76

Tree-SHA512: b828a99780614a9b74f7a9c347ce0687de6f8d75232840f5ffc26e02bbb25a3b1f5f9deabbe44f82ada01459586ee8452a3ee2da05d1b3c48558c8df6f49e1b1

test/sanitizer_suppressions/tsan

@@ -13,7 +13,7 @@ race:zmq::*
 race:bitcoin-qt
 
 # deadlock (TODO fix)
-deadlock:CChainState::ConnectTip
+deadlock:Chainstate::ConnectTip
 
 # Intentional deadlock in tests
 deadlock:sync_tests::potential_deadlock_detected