always expose dup3 and pipe2

they will be in the next version of POSIX

include/unistd.h

@@ -33,9 +33,11 @@ extern "C" {
 #include <bits/alltypes.h>
 
 int pipe(int [2]);
+int pipe2(int [2], int);
 int close(int);
 int dup(int);
 int dup2(int, int);
+int dup3(int, int, int);
 off_t lseek(int, off_t, int);
 int fsync(int);
 int fdatasync(int);
@@ -182,8 +184,6 @@ int setresgid(gid_t, gid_t, gid_t);
 int getresuid(uid_t *, uid_t *, uid_t *);
 int getresgid(gid_t *, gid_t *, gid_t *);
 char *get_current_dir_name(void);
-int pipe2(int [2], int);
-int dup3(int, int, int);
 void syncfs(int);
 #endif