USBPhyHw: remove mbed.h inclusion

[0xc0170]

Summary of changes

Remove user facing header file, it should not be included within a library. The header itself does not need anything from Mbed.

It could possibly fail if targets which implement usb are not including what is required for their implementation.

I can fix any breakage in nightly but before that I'll run with this PR couple of builds for targets with usb support.

Impact of changes

Migration actions required

Documentation

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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

[x] No Tests required for this change (E.g docs only update)
[] Covered by existing mbed-os tests (Greentea or Unittest)
[] Tests / results supplied as part of this PR

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Reviewers

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[ciarmcom]

@0xc0170, thank you for your changes.
@maclobdell @ARMmbed/mbed-os-maintainers please review.

[0xc0170]

I could reproduce events failures, as I wrote earlier, I'll run some tests locally and fix includes in USB HAL.

[0xc0170]

I'll run one CI to get the better coverage what failures are there so can fix it quickly

[mbed-ci]

Jenkins CI Test : ✔️ SUCCESS

Build Number: 1 | 🔒 Jenkins CI Job | 🌐 Logs & Artifacts

CLICK for Detailed Summary

jobs	Status
jenkins-ci/mbed-os-ci_unittests	✔️
jenkins-ci/mbed-os-ci_build-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-ARM	✔️
jenkins-ci/mbed-os-ci_greentea-test	✔️
jenkins-ci/mbed-os-ci_dynamic-memory-usage	✔️
jenkins-ci/mbed-os-ci_cloud-client-pytest	✔️

[0xc0170]

Travis restarted

[0xc0170]

@adbridge please review, and merge if all OK