move syscall constants for networking into net space to avoid windows build issue

src/syscall/net.go

@@ -32,16 +32,3 @@ type Conn interface {
 	// SyscallConn returns a raw network connection.
 	SyscallConn() (RawConn, error)
 }
-
-const (
-	AF_INET       = 0x2
-	SOCK_STREAM   = 0x1
-	SOCK_DGRAM    = 0x2
-	SOL_SOCKET    = 0x1
-	SO_KEEPALIVE  = 0x9
-	SOL_TCP       = 0x6
-	TCP_KEEPINTVL = 0x5
-	IPPROTO_TCP   = 0x6
-	IPPROTO_UDP   = 0x11
-	F_SETFL       = 0x4
-)

src/syscall/syscall_libc_darwin.go

@@ -53,6 +53,7 @@ const (
 	DT_UNKNOWN = 0x0
 	DT_WHT     = 0xe
 	F_GETFL    = 0x3
+	F_SETFL    = 0x4
 	O_NONBLOCK = 0x4
 )
 

src/syscall/syscall_libc_wasi.go

@@ -102,6 +102,7 @@ const (
 
 	// ../../lib/wasi-libc/expected/wasm32-wasi/predefined-macros.txt
 	F_GETFL = 3
+	F_SETFL = 4
 )
 
 // These values are needed as a stub until Go supports WASI as a full target.