Kernel: Use Userspace<T> for the bind syscall, and implementation

Author: https://github.com/bgianfo
Commit: 02660b5d60
Pull-request: https://github.com/SerenityOS/serenity/pull/3062
Reviewed-by: https://github.com/awesomekling

Kernel/Net/IPv4Socket.h

@@ -49,7 +49,7 @@ public:
     static Lockable<HashTable<IPv4Socket*>>& all_sockets();
 
     virtual KResult close() override;
-    virtual KResult bind(const sockaddr*, socklen_t) override;
+    virtual KResult bind(Userspace<const sockaddr*>, socklen_t) override;
     virtual KResult connect(FileDescription&, const sockaddr*, socklen_t, ShouldBlock = ShouldBlock::Yes) override;
     virtual KResult listen(size_t) override;
     virtual void get_local_address(sockaddr*, socklen_t*) override;