Merge changes from topic "nnapi-cherrypick-from-pi-to-aosp"

* changes:
  Validate strided slice output dims in cpu executor
  Fix setOperandValue validation for optional operands.
  Reduce OpenMP thread busywait time (200 to 1 ms)
  Fix tests that are to only use public API to do so
  Unknown dimension tests for partitioning and hvx
tree: 24af030b5ca00218df7040a803bfe5a0a431f67c
  1. nn/
  2. CleanSpec.mk
  3. OWNERS