NeuralNetworks: pin cpp_std to gnu++17 am: 9e136a0ea1 am: 2005d6bf8c

Original change: https://android-review.googlesource.com/c/platform/packages/modules/NeuralNetworks/+/2833230

Change-Id: I0f18f995fdf0a24c120ec30db642084c508e97d9
Signed-off-by: Automerger Merge Worker <[email protected]>