Corrected support for 16-bit systems

We still need access to a 16-bit system to correctly test
these changes.

ltable.c

@@ -257,9 +257,11 @@ LUAI_FUNC unsigned int luaH_realasize (const Table *t) {
     size |= (size >> 2);
     size |= (size >> 4);
     size |= (size >> 8);
+#if (UINT_MAX >> 14) > 3  /* unsigned int has more than 16 bits */
     size |= (size >> 16);
 #if (UINT_MAX >> 30) > 3
     size |= (size >> 32);  /* unsigned int has more than 32 bits */
+#endif
 #endif
     size++;
     lua_assert(ispow2(size) && size/2 < t->alimit && t->alimit < size);