Remove ITM Trace support from Arduino Nano 33 BLE

[manchoz]

Description

Remove ITM Trace support from Arduino Nano 33 BLE target definition.

Summary of change

Arduino Nano 33 BLE doesn't expose ITM Trace pins which instead are used for external I2C.

When ITM trace is enabled applications need to reset both CoreDebug->DEMCR and NRF_CLOCK->TRACECONFIG in user code to get I2C working. CoreDebug->DEMCR and NRF_CLOCK->TRACECONFIG are otherwise configured at SystemInit.

This patch removes ITM from target features.

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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

[ciarmcom]

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

[0xc0170]

CI started

[mbed-ci]

Test run: SUCCESS

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