post_proc: fix offload PBE failure in sending calibration to lpass

PBE values are misinterpreted when transferring from u to k via
mixer ctl interface. Config values have to be copied one by one rather
than copying through continuous memory.

CRs-Fixed: 2456844
Change-Id: Icf19d02ec1717318e80a8a3859c165eae42c000d