Added API to reset MAC statistics and Wi-SUN statistics

[debdeep-arm]

Summary of changes

Added API to reset MAC statistics and Wi-SUN statistics.
This is copied from #14439

Impact of changes

Migration actions required

Documentation

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Pull request type

[] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[X] Feature update (New feature / Functionality change / New API)
[] Major update (Breaking change E.g. Return code change / API behaviour change)

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Test results

[] No Tests required for this change (E.g docs only update)
[X] Covered by existing mbed-os tests (Greentea or Unittest)
[] Tests / results supplied as part of this PR

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Reviewers

@artokin

[ciarmcom]

@debdeep-arm, thank you for your changes.
@artokin @ARMmbed/mbed-os-mesh @ARMmbed/mbed-os-maintainers please review.

[0xc0170]

CI started

[mbed-ci]

Jenkins CI Test : ✔️ SUCCESS

Build Number: 1 | 🔒 Jenkins CI Job | 🌐 Logs & Artifacts

CLICK for Detailed Summary

jobs	Status
jenkins-ci/mbed-os-ci_unittests	✔️
jenkins-ci/mbed-os-ci_build-cloud-example-ARM	✔️
jenkins-ci/mbed-os-ci_cmake-cloud-example-ARM	✔️
jenkins-ci/mbed-os-ci_cmake-cloud-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-cloud-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_cmake-example-ARM	✔️
jenkins-ci/mbed-os-ci_build-example-ARM	✔️
jenkins-ci/mbed-os-ci_build-greentea-ARM	✔️
jenkins-ci/mbed-os-ci_build-greentea-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_cmake-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_greentea-test	✔️

[debdeep-arm]

Hi @0xc0170, can we merge this in ?

[0xc0170]

@debdeep-arm We are waiting for the release to complete and we will merge all "ready for merge" pull requests (eta: later today)