openssh: add cosmetic patch to silence 'no such identity: xxxx' errors

after update to openssh-6.2p1 there is an annoying error message on every connect.
```
no such identity: /storage/.ssh/id_rsa: No such file or directory
no such identity: /storage/.ssh/id_dsa: No such file or directory
```

the error should be printed only in debug level 3 (ssh -vvv). this cosmetial patch restores the old behaviour.