Steps to reproduce:

* Create a datadir that is pruned
* Start with `-prune=550 -reindex-chainstate`
* Hangs with idle CPU

(`-reindex` works)
#include <utilstrencodings.h>
#include <utilstring.h>
#include <utilsyscall_sandbox.h>
#include <utilsystem.h>
#include <utilthread.h>
#include <utilthreadnames.h>
#include <utiltranslation.h>
#include <validation.h>
#include <validationinterface.h>
#include <walletinitinterface.h>
#include <condition_variable>
#include <cstdint>
#include <cstdio>
#include <fstream>
#include <functional>
#include <set>
#include <string>
#include <thread>
#include <vector>
#ifndef WIN32
#include <attributes.h>
#include <cerrno>
#include <signal.h>
#include <sysstat.h>
#endif
#include <boostalgorithmstringreplace.hpp>
#include <boostsignals2signal.hpp>
#if ENABLE_ZMQ
#include <zmqzmqabstractnotifier.h>
#include <zmqzmqnotificationinterface.h>