Collect built-in LWLock tranche names statically, not dynamically.

There is little point in using the LWLockRegisterTranche mechanism for
built-in tranche names.  It wastes cycles, it creates opportunities for
bugs (since failing to register a tranche name is a very hard-to-detect
problem), and the lack of any centralized list of names encourages
sloppy nonconformity in name choices.  Moreover, since we have a
centralized list of the tranches anyway in enum BuiltinTrancheIds, we're
certainly not buying any flexibility in return for these disadvantages.

Hence, nuke all the backend-internal LWLockRegisterTranche calls,
and instead provide a const array of the builtin tranche names.

(I have in mind to change a bunch of these names shortly, but this
patch is just about getting them into one place.)

Discussion: https://postgr.es/m/9056.1589419765@sss.pgh.pa.us

src/backend/access/transam/slru.c

@@ -235,9 +235,6 @@ SimpleLruInit(SlruCtl ctl, const char *name, int nslots, int nlsns,
 	else
 		Assert(found);
 
-	/* Register SLRU tranche in the main tranches array */
-	LWLockRegisterTranche(tranche_id, name);
-
 	/*
 	 * Initialize the unshared control struct, including directory path. We
 	 * assume caller set PagePrecedes.

src/backend/access/transam/xlog.c

@@ -5116,10 +5116,8 @@ XLOGShmemInit(void)
 		/* both should be present or neither */
 		Assert(foundCFile && foundXLog);
 
-		/* Initialize local copy of WALInsertLocks and register the tranche */
+		/* Initialize local copy of WALInsertLocks */
 		WALInsertLocks = XLogCtl->Insert.WALInsertLocks;
-		LWLockRegisterTranche(LWTRANCHE_WAL_INSERT,
-							  "wal_insert");
 
 		if (localControlFile)
 			pfree(localControlFile);
@@ -5155,7 +5153,6 @@ XLOGShmemInit(void)
 		(WALInsertLockPadded *) allocptr;
 	allocptr += sizeof(WALInsertLockPadded) * NUM_XLOGINSERT_LOCKS;
 
-	LWLockRegisterTranche(LWTRANCHE_WAL_INSERT, "wal_insert");
 	for (i = 0; i < NUM_XLOGINSERT_LOCKS; i++)
 	{
 		LWLockInitialize(&WALInsertLocks[i].l.lock, LWTRANCHE_WAL_INSERT);

src/backend/replication/logical/origin.c

@@ -517,9 +517,6 @@ ReplicationOriginShmemInit(void)
 			ConditionVariableInit(&replication_states[i].origin_cv);
 		}
 	}
-
-	LWLockRegisterTranche(replication_states_ctl->tranche_id,
-						  "replication_origin");
 }
 
 /* ---------------------------------------------------------------------------

src/backend/replication/slot.c

@@ -140,9 +140,6 @@ ReplicationSlotsShmemInit(void)
 		ShmemInitStruct("ReplicationSlot Ctl", ReplicationSlotsShmemSize(),
 						&found);
 
-	LWLockRegisterTranche(LWTRANCHE_REPLICATION_SLOT_IO_IN_PROGRESS,
-						  "replication_slot_io");
-
 	if (!found)
 	{
 		int			i;

src/backend/storage/buffer/buf_init.c

@@ -87,9 +87,6 @@ InitBufferPool(void)
 						NBuffers * (Size) sizeof(LWLockMinimallyPadded),
 						&foundIOLocks);
 
-	LWLockRegisterTranche(LWTRANCHE_BUFFER_IO_IN_PROGRESS, "buffer_io");
-	LWLockRegisterTranche(LWTRANCHE_BUFFER_CONTENT, "buffer_content");
-
 	/*
 	 * The array used to sort to-be-checkpointed buffer ids is located in
 	 * shared memory, to avoid having to allocate significant amounts of

src/backend/storage/ipc/procarray.c

@@ -267,8 +267,6 @@ CreateSharedProcArray(void)
 							mul_size(sizeof(bool), TOTAL_MAX_CACHED_SUBXIDS),
 							&found);
 	}
-
-	LWLockRegisterTranche(LWTRANCHE_PROC, "proc");
 }
 
 /*