Add a few more missing prototypes to the SunOS 4.1.4 section (no SF

bugreport, just an IRC one by Marion Delgado.) These prototypes are
necessary because the functions are tossed around, not just called.

Modules/posixmodule.c

@@ -113,6 +113,9 @@ corresponding Unix manual entries for more information on calls.";
 extern int rename(const char *, const char *);
 extern int pclose(FILE *);
 extern int fclose(FILE *);
+extern int fsync(int);
+extern int lstat(const char *, struct stat *);
+extern int symlink(const char *, const char *);
 #endif
 
 #ifdef NeXT