[BLE] Update parameters passed to onDataSent, onUpdatesEnabled/Disabled, and onConfirmationReceived callbacks

[AGlass0fMilk]

Summary of changes

Update parameters passed to onDataSent, onUpdatesEnabled/Disabled, and onConfirmationReceived callbacks.

Each of these callbacks are now given the related connection ID and attribute handle.

Individual callback-registering functions in the GattServer API are deprecated by this PR.

Resolves #13726

Impact of changes

Any use of GattServer::onDataSent, GattServer::onUpdatesEnabled, GattServer::onUpdatesDisabled, GattServer::onConfirmationReceived is now deprecated and will be removed in a future release.

Migration actions required

Update applications calling the deprecated functions to use the new GattServer::EventHandler API.

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

@pan- @paul-szczepanek-arm

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[ciarmcom]

@AGlass0fMilk, thank you for your changes.
@paul-szczepanek-arm @pan- @ARMmbed/mbed-os-maintainers please review.

[pan-]

I'm not in favor of doing a breaking change right now.
To move this PR forward can you add callbacks into the EventHandler class and mark the onXXX as deprecated ?

Pull request has been modified.

[AGlass0fMilk]

@pan- I have implemented changes to deprecate the individual callback-registering functions in GattServer and have introduced new ones with more flexible parameters in the GattServer::EventHandler API.

[pan-]

@AGlass0fMilk Thank you for the PR. It all looks good except for one thing. Can you use const references instead of const pointers for callback parameters in EventHandler ?
I would prefer to remain consistent with what has been done in Gap::EventHandler

[AGlass0fMilk]

@AGlass0fMilk Thank you for the PR. It all looks good except for one thing. Can you use const references instead of const pointers for callback parameters in EventHandler ?
I would prefer to remain consistent with what has been done in Gap::EventHandler

See 862669c

Pull request has been modified.

[pan-]

You probably want to update the call site too. Passing pointers won't work.

[AGlass0fMilk]

Merging this with #13734 since they are closely tied.