Generalize FULLY_CONNECTED op to support input product scale > output scale

To remove inconsistency with TF Lite.
TF Lite removed input/output scale restrictions to support additional
use cases. This is a superset of existing FULLY_CONNECTED functionality.

Bug: 127427474
Test: NeuralNetworksTest_static
Change-Id: Icf38945f4c441f56090f40fa2b844240f2e6c49e
13 files changed