Remove the deprecated Ticker APIs

[rajkan01]

Summary of changes

• Removed the Ticker deprecated APIs
• Updated the async greentea test to use attach with callback API

Impact of changes

Breaking change: Ticker attach and attach_us methods with cv-qualifiers have been deprecated since Mbed OS 5.1 and they are removed now.

Migration actions required

Use attach(callback(obj, method), t) and attach_us(callback(obj, method), t)

Documentation

None

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Pull request type

[] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[] Feature update (New feature / Functionality change / New API)
[x] 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

@evedon @bulislaw

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[0xc0170]

CI started

[mbed-ci]

Test run: SUCCESS

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