Revert "Remove old-style build tags"

This reverts commit 11ae25660a.

client-nowasm_test.go

@@ -1,4 +1,5 @@
 //go:build !wasm
+// +build !wasm
 
 package torrent
 

iplist/packed.go

@@ -1,4 +1,5 @@
 //go:build !wasm
+// +build !wasm
 
 package iplist
 

issue211_test.go

@@ -1,4 +1,5 @@
 //go:build !wasm
+// +build !wasm
 
 package torrent
 

storage/bolt-piece-completion.go

@@ -1,4 +1,5 @@
 //go:build !noboltdb && !wasm
+// +build !noboltdb,!wasm
 
 package storage
 

storage/bolt-piece.go

@@ -1,4 +1,5 @@
 //go:build !noboltdb && !wasm
+// +build !noboltdb,!wasm
 
 package storage
 

storage/bolt.go

@@ -1,4 +1,5 @@
 //go:build !noboltdb && !wasm
+// +build !noboltdb,!wasm
 
 package storage
 

storage/default-dir-piece-completion-sqlite.go

@@ -1,4 +1,5 @@
 //go:build cgo && !nosqlite
+// +build cgo,!nosqlite
 
 package storage
 

storage/mmap.go

@@ -1,4 +1,5 @@
 //go:build !wasm
+// +build !wasm
 
 package storage
 

storage/sqlite-piece-completion.go

@@ -1,4 +1,5 @@
 //go:build cgo && !nosqlite
+// +build cgo,!nosqlite
 
 package storage
 

storage/sqlite/direct.go

@@ -1,4 +1,5 @@
 //go:build cgo
+// +build cgo
 
 package sqliteStorage
 

storage/sqlite/sqlite-storage_test.go

@@ -1,4 +1,5 @@
 //go:build cgo
+// +build cgo
 
 package sqliteStorage
 

torrent_mmap_test.go

@@ -1,4 +1,5 @@
 //go:build !wasm
+// +build !wasm
 
 package torrent
 

utp_libutp.go

@@ -1,9 +1,10 @@
 //go:build cgo && !disable_libutp
+// +build cgo,!disable_libutp
 
 package torrent
 
 import (
-	utp "github.com/anacrolix/go-libutp"
+	"github.com/anacrolix/go-libutp"
 )
 
 func NewUtpSocket(network, addr string, fc firewallCallback) (utpSocket, error) {