Move mbed-coap to connectivity/libraries

[LDong-Arm]

Summary of changes

As per our new directory structure proposal, this PR moves mbed-coap from features/frameworks into connectivity/libraries.

Impact of changes

Migration actions required

Documentation

None.

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Pull request type

[x] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[] 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)
[x] Tests / results supplied as part of this PR

nanostack-border-router compiles for K64F. Unit tests continue to work.

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Reviewers

@ARMmbed/mbed-os-core @bulislaw @0xc0170

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[ciarmcom]

@LDong-Arm, thank you for your changes.
@ARMmbed/mbed-os-maintainers please review.

[pan-]

There is now two PRs to move mbed-coap some place else: #12962

[LDong-Arm]

There is now two PRs to move mbed-coap some place else: #12962

My PR is to put mbed-coap in the place we agreed - connectivity/libraries/mbed-coap. Once it gets in, #12962 can then be reworked to do connectivity/libraries/mbed-coap -> connectivity/libraries/FEATURE_MBED_COAP/ as its main point is to use the "FEATURE_..." magic name.

[rajkan01]

LGTM

[evedon]

There is now two PRs to move mbed-coap some place else: #12962

My PR is to put mbed-coap in the place we agreed - connectivity/libraries/mbed-coap. Once it gets in, #12962 can then be reworked to do connectivity/libraries/mbed-coap -> connectivity/libraries/FEATURE_MBED_COAP/ as its main point is to use the "FEATURE_..." magic name.

I don't think we want to use "FEATURE_..." magic name going forward.

[adbridge]

CI started

[mbed-ci]

Test run: SUCCESS

Summary: 6 of 6 test jobs passed
Build number : 1
Build artifacts