Remove qcrypto interface for hammerhead.

The hw crypto interface breaks l2tp vpn. And the dm engine in
hammerhead doesn't use the hw qcrypto interface. So, disable qcrypto.
The l2tp will use openssl software crypto, original aosp does this too.

Change-Id: I8f3f5005b2f9b7a0797ba2ebec77c4501a09aaf7
Merge pull request #5 from CyanogenMod/cm-11.0

Remove qcrypto interface for hammerhead.