dlx: Disable entropy gathering for MMC device

 * Flash devices aren't a good source of entropy and contributing to the
   pool can be an expensive operation requiring needless locking.

Change-Id: I3dbc245ee9f6de37c84eeabe12c0f0ed6272878b
dlx: libaudioamp: Add initialization function stubs

Change-Id: I34aad7e268dbb59edb0d6c224f5f95cc75e405fa