Add missing libroot stub on x86 (different from x86_64).

src/system/libroot/stubbed/libroot_stubs.c

@@ -1244,6 +1244,7 @@ void __tgammal() {}
 void __times() {}
 void __times_beos() {}
 void __tls_get_addr() {}
+void ___tls_get_addr() {}
 void __trunc() {}
 void __truncf() {}
 void __truncl() {}