always truncate when SyncWrites is enabled

This will delete values that were in the process of being "put" when we crashed
but that's likely expected behavior anyways. Without this, ipfs on badger may
refuse to start after a crash.

datastore.go

@@ -53,7 +53,7 @@ func NewDatastore(path string, options *Options) (*Datastore, error) {
 		gcDiscardRatio = options.gcDiscardRatio
 	}
 
-	if osh.IsWindows() && opt.SyncWrites {
+	if opt.SyncWrites {
 		opt.Truncate = true
 	}