core/rawdb: improve freezerTable.Sync (#26245)

While investigating #22374, I noticed that the Sync operation of the
freezer does not take the table lock. It also doesn't call sync for all files
if there is an error with one of them. I doubt this will fix anything, but
didn't want to drop the fix on the floor either.

core/rawdb/freezer_table.go

@@ -867,13 +867,20 @@ func (t *freezerTable) advanceHead() error {
 // Sync pushes any pending data from memory out to disk. This is an expensive
 // operation, so use it with care.
 func (t *freezerTable) Sync() error {
-	if err := t.index.Sync(); err != nil {
-		return err
-	}
-	if err := t.meta.Sync(); err != nil {
-		return err
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	var err error
+	trackError := func(e error) {
+		if e != nil && err == nil {
+			err = e
+		}
 	}
-	return t.head.Sync()
+
+	trackError(t.index.Sync())
+	trackError(t.meta.Sync())
+	trackError(t.head.Sync())
+	return err
 }
 
 func (t *freezerTable) dumpIndexStdout(start, stop int64) {