[feature-wisun] Replaced new calls with nothrow version of the call on mesh api

[mikaleppanen]

Summary of changes

Replaced new calls with no throw version of the call.

Impact of changes

None

Migration actions required

None

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)
[] Tests / results supplied as part of this PR

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Reviewers

@mikter @artokin

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[adbridge]

CI started

[mbed-ci]

Test run: FAILED

Summary: 1 of 10 test jobs failed
Build number : 1
Build artifacts

Failed test jobs:

• jenkins-ci/mbed-os-ci_greentea-test-lts

[0xc0170]

CI restarted

[mbed-ci]

Test run: SUCCESS

Summary: 10 of 10 test jobs passed
Build number : 2
Build artifacts