Deprecates NVStore

[VeijoPesonen]

Description (required)

Marks the existing NVStore implementation as deprecated. The implementation will be removed on the next major release. Users are expected to migrate on KVStore instead if they are looking for similar storage solution.

Summary of change (What the change is for and why)

NVStore API is marked as deprecated.

Documentation (Details of any document updates required)

NVStore shouldn't be mentioned anywhere in our documentation from the next major release onwards.

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Pull request type (required)

[] 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 (required)

[] 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 (optional)

@SeppoTakalo
@JanneKiiskila

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Release Notes (required for feature/major PRs)

Summary of changes

NVStore is marked as deprecated

Impact of changes

NVStore won't be available from the next major release onwards

Migration actions required

Users must switch to use KVStore. For documentation please see Docs › APIs › Storage › KVStore

[mbed-ci]

Test run: SUCCESS

Summary: 11 of 11 test jobs passed
Build number : 1
Build artifacts

[0xc0170]

[X] Feature update (New feature / Functionality change / New API)

This one should have "Release notes" - this deprecation should be there - please fill in details

[VeijoPesonen]

@0xc0170 Release notes-section updated as requested.

[0xc0170]

Not certain why jenkins failed to update the hook, I restarted the test

[adbridge]

@VeijoPesonen Could you please fill in the Description section properly. Please refer to the guiding notes if you are unsure of how. Thanks.

[VeijoPesonen]

@VeijoPesonen Could you please fill in the Description section properly. Please refer to the guiding notes if you are unsure of how. Thanks.

@adbridge, description added. Please let me know if something relevant is still missing.

[adbridge]

@VeijoPesonen thank you for adding the description. Are there any specific migration issues users may face having to move from using NVStore to KVStore? Should the migration section point them to any documentation to help ? Remember all the Release Notes section gets published with the Minor release.

[VeijoPesonen]

Are there any specific migration issues users may face having to move from using NVStore to KVStore?

Not that I know of. @teetak01, @TeroJaasko Are you aware of any possible issues?

[JanneKiiskila]

There is no migration story, as far as I know. So, it is a hard break and whomever is using NVStore -> can't update to an Mbed OS without NVStore support anymore.

[mbed-ci]

Test run: SUCCESS

Summary: 11 of 11 test jobs passed
Build number : 2
Build artifacts