Add float16 support to CONV_2D

Fix: 118608196
Test: NeuralNetworksTest_static
Change-Id: I345af1e1fbdd0a510875ae834f94863bcdbeeb52
Merged-In: I345af1e1fbdd0a510875ae834f94863bcdbeeb52
(cherry-picked from 7e6c1238d25be27ddf8df8848dde85ab1f62aef4)
11 files changed