hammerhead: readd DSP library

Change-Id: Ie233ab8e6e9dc6146a2da02610f1bf0bb55f1129
hammerhead: Do not build Torch app anymore

not needed in LP due of native API

Change-Id: I3fcddffb195f5723add5bee4ed3e9949221c2221
Merge remote-tracking branch 'slim/lp5.0' into lp