Refactor generated NNAPI tests

See change I2c0366fb87c96851fa6e0f8fe9ceac012d8e3513

Bug: 136097638
Test: m VtsHalNeuralnetworksV1_0TargetTest
Test: m VtsHalNeuralnetworksV1_1TargetTest
Test: m VtsHalNeuralnetworksV1_2TargetTest
Test: m VtsHalNeuralnetworksV1_2CompatV1_0TargetTest
Change-Id: I6fdede028422145d313d46532b5d2154ef0d40bc
Merged-In: I6fdede028422145d313d46532b5d2154ef0d40bc
(cherry picked from commit 2bcfdc82a0172d42202d3b3bc4dab98d8cc0ff58)
19 files changed