Revert pg_wal_replay_wait() stored procedure

This commit reverts 3c5db1d6b0, and subsequent improvements and fixes
including 8036d73ae3, 867d396ccd, 3ac3ec580c, 0868d7ae70, 85b98b8d5a,
2520226c95, 014f9f34d2, e658038772, e1555645d7, 5035172e4a, 6cfebfe88b,
73da6b8d1b, and e546989a26.

The reason for reverting is a set of remaining issues.  Most notably, the
stored procedure appears to need more effort than the utility statement
to turn the backend into a "snapshot-less" state.  This makes an approach
to use stored procedures questionable.

Catversion is bumped.

Discussion: https://postgr.es/m/Zyhj2anOPRKtb0xW%40paquier.xyz

src/backend/access/transam/xlogrecovery.c

@@ -40,7 +40,6 @@
 #include "access/xlogreader.h"
 #include "access/xlogrecovery.h"
 #include "access/xlogutils.h"
-#include "access/xlogwait.h"
 #include "backup/basebackup.h"
 #include "catalog/pg_control.h"
 #include "commands/tablespace.h"
@@ -1829,16 +1828,6 @@ PerformWalRecovery(void)
 				break;
 			}
 
-			/*
-			 * If we replayed an LSN that someone was waiting for then walk
-			 * over the shared memory array and set latches to notify the
-			 * waiters.
-			 */
-			if (waitLSNState &&
-				(XLogRecoveryCtl->lastReplayedEndRecPtr >=
-				 pg_atomic_read_u64(&waitLSNState->minWaitedLSN)))
-				WaitLSNWakeup(XLogRecoveryCtl->lastReplayedEndRecPtr);
-
 			/* Else, try to fetch the next WAL record */
 			record = ReadRecord(xlogprefetcher, LOG, false, replayTLI);
 		} while (record != NULL);