Fix stale NNAPI documentation

The scale and zeroPoint fields are applicable to other types since 1.2.

Also makes some whitespaces changes due to the generated documentation
getting out of sync with the template in frameworks/ml/nn.

Fix: 160406237
Test: generate_api.sh
Test: m
Change-Id: Icf594d40c73ff8c05044c320ac9eb6a9c5a89754
Merged-In: Icf594d40c73ff8c05044c320ac9eb6a9c5a89754
(cherry picked from commit 0d6cefe9)