Make libnosys function stubs part of libnacl

src/untrusted/nacl/stubs/isatty.c

Index: src/untrusted/nacl/stubs/isatty.c
diff --git a/src/untrusted/nosys/isatty.c b/src/untrusted/nacl/stubs/isatty.c
similarity index 83%
rename from src/untrusted/nosys/isatty.c
rename to src/untrusted/nacl/stubs/isatty.c
index 1bfc832bea5c23b21be31615d175dfb0d19015c2..a87647b766c4941f1088719fffa58cd26208cb81 100644
--- a/src/untrusted/nosys/isatty.c
+++ b/src/untrusted/nacl/stubs/isatty.c
@@ -16,6 +16,3 @@ int isatty(int file) {
   /* isatty does not have an error return, so we simply say `no' always. */
   return 0;
 }
-
-#include "native_client/src/untrusted/nosys/warning.h"
-stub_warning(isatty);