Bug #25097 mysql_server_init fails silently if no errmsg.sys is present.

There was no way to return an error from the client library
if no MYSQL connections was established.
So here i added variables to store that king of errors and
made functions like mysql_error(NULL) to return these.

client/mysql.cc

@@ -420,6 +420,7 @@ int main(int argc,char *argv[])
   }
   if (mysql_server_init(emb_argc, emb_argv, (char**) server_default_groups))
   {
+    put_error(NULL);
     free_defaults(defaults_argv);
     my_end(0);
     exit(1);