Kernel: Use Userspace<T> for the open syscall

Kernel/Process.h

@@ -211,7 +211,7 @@ public:
     int sys$getresuid(uid_t*, uid_t*, uid_t*);
     int sys$getresgid(gid_t*, gid_t*, gid_t*);
     mode_t sys$umask(mode_t);
-    int sys$open(const Syscall::SC_open_params*);
+    int sys$open(Userspace<const Syscall::SC_open_params*>);
     int sys$close(int fd);
     ssize_t sys$read(int fd, Userspace<u8*>, ssize_t);
     ssize_t sys$write(int fd, const u8*, ssize_t);

Kernel/Syscalls/open.cpp

@@ -31,7 +31,7 @@
 
 namespace Kernel {
 
-int Process::sys$open(const Syscall::SC_open_params* user_params)
+int Process::sys$open(Userspace<const Syscall::SC_open_params*> user_params)
 {
     Syscall::SC_open_params params;
     if (!validate_read_and_copy_typed(&params, user_params))