@tensorflow/micro

Flatten namespace for kernel operator RESHAPE

Update unit tests namespace usage

Update MicroOpResolver namespace usage

bug=fixes #2105

@tensorflow/micro

Remove conditional compilation for kernel tests for the following platforms: Xtensa
Add optimized kernel reference fallback code for the following platforms: Xtensa

Resolves: `TODO(b/237407410): Re-enable for Vision P6 when the issue is resolved`

The following table shows the size changes for each benchmark binary as a result of this PR:
| Platform | Benchmark | Build | Text | Data | BSS |
| --- | --- | --- | --- | --- | --- |
| hifi4 | keyword | default | 0 | 0 | 0 |
| hifi5 | keyword | default | 0 | 0 | 0 |
| p6 | keyword | default | 0 | 0 | 0 |
| hifi4 | person detection | default | +40 | +32 | 0 |
| hifi5 | person detection | default | +16 | +32 | 0 |
| p6 | person detection | default | +64 | +0 | 0 |

bug=fixes #1770

* Added Support for Reshape int8 on Vision P6

Added Support for Reshape int8 on Vision P6

* Use C++ style comments
Co-authored-by: NTing Yan <94130036+tingyan19@users.noreply.github.com>
Co-authored-by: Nmergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

* Added Support for INT8 pad

BUG= Added support for INT8 Pad
 Fixed padding issues in conv for larger tiles

* Reverted submits to main

* Revert "Added Support for INT8 pad"

This reverts commit fdc6e1d624609041b8b743563613339948ff70da.

* Added Support for INT8 Pad

BUG= Added support for INT8 Pad. Fixed padding issue in conv.

* TFLITE_DCHECK xiPadGetMemReqd_Context() status
Co-authored-by: NTing Yan <94130036+tingyan19@users.noreply.github.com>

* Refactor to share code between reference and optimized kernels.

The goal is to reduce code duplication, improve readability of the
optimized kernels and reduce the maintenance overhead.

* Fix bazel build (and hopefully others as well).
Co-authored-by: NPauline Sho <psho@google.com>

* BUG= Added Support for ReduceMax on Vision P6

* BUG= Updated for namespace use

* BUG= Fixed build issue for non VP6 cores

* updated as per the review comments
Co-authored-by: NTing Yan <94130036+tingyan19@users.noreply.github.com>