Display full path of generated coverage output from unittests.

[SeppoTakalo]

Description (required)

When running unittests with --coverage option, it only tells you that code coverage report created. but without specifying where it went.

This small change makes it verbose to show where the coverage output was generated. Easier for end user to find it.

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

Display full path of generated coverage output from unittests.

Pull request type (required)

[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 (required)

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

$ mbed test --unittest --coverage both

...

100% tests passed, 0 tests failed out of 47

Total Test time (real) =   0.51 sec




HTML code coverage report created in /Users/seppo/src/mbed-os/BUILD/unittests/coverage/index.html


XML code coverage report created in /Users/seppo/src/mbed-os/BUILD/unittests/coverage.xml

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Reviewers (optional)

@ARMmbed/mbed-os-test

[ciarmcom]

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

[mbed-ci]

Test run: SUCCESS

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

[OPpuolitaival]

Looks good!

[SeppoTakalo]

Why "travis-ci/pr" does not finish?

[0xc0170]

Sometimes the hook is not updated, I'll restart it