Remove heat::db from all the components of the module.

This patch is needed to completely remove any require heat::db that
point to heat::db that was removed in change:
I4584cdb12d1f9e624228e6ee34b4bcfbf649a12e

The patch is connected to the fact that in the cited change we
missed those references.

Change-Id: Idd9dcefd52c63e9c8cd74fc39bc4b7ba04f981bc