Added Wi-SUN statistics interface

[mikaleppanen]

Summary of changes

This is port of #12766 to Mbed OS master.

Added network, physical layer, MAC and FHSS statistics to Wi-SUN interface. There are new functions to enable/disable and read the statistics.

Impact of changes

None

Migration actions required

None

Documentation

None

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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

@mikter @JarkkoPaso @artokin @juhhei01

[0xc0170]

@mikaleppanen Can you check why psa faileD? I restarted it, the error does not have anything with this PR, does this PR needs rebase now? Please do

[juhhei01]

@0xc0170 We not even use PSA so interesting that we may break that.

[juhhei01]

@0xc0170 looks like CI machine problem0.00s$ source_pkg gcc
install.2
2100.00s$ arm-none-eabi-gcc --version
install.3
2161.42s$ python -m pip install --upgrade pip==18.1
install.4
2241.03s$ python -m pip install --upgrade setuptools==40.4.3
install.5
23218.76s$ pip install -r requirements.txt
install.6
3300.27s$ pip list --verbose
3990.02s$ python tools/psa/generate_partition_code.py
400python: can't open file 'tools/psa/generate_partition_code.py': [Errno 2] No such file or directory
401The command "python tools/psa/generate_partition_code.py" exited with 2.
4020.02s$ git diff --exit-code
403The command "git diff --exit-code" exited with 0.

Pull request has been modified.

[mikaleppanen]

@0xc0170 Rebased over latest master.

[adbridge]

@mikter @0xc0170 could you guys re-review this please?

[mergify]

This PR cannot be merged due to conflicts. Please rebase to resolve them.

[mikaleppanen]

Rebased over master.

[0xc0170]

CI started

[mbed-ci]

Test run: SUCCESS

Summary: 7 of 7 test jobs passed
Build number : 1
Build artifacts