Remove unsupported targets

[MarceloSalazar]

Summary of changes

This is the first of a series of PRs to remove targets that are not supported or retired as explained in recent blog post.

There are individual commits to remove targets from targets.json and files/folders for the corresponding targets.

Impact of changes

The following targets are being removed:

• Thundersoft (all)
• Realtek RTL8195A
• Ublox ODIN and related (OKDO, MTB)
• RDA (all)
• Gigadevice GD32_E103VB
• Atmel (all)
• TI (all)
• Etteplan Elmo
• Wiznet (all)
• Silica
• Renesas VK_RZ_A1H
• Rename MTB_MXCHIP_EMW3166 to WIO_EMW3166
• VBLUNO51 and VBLUNO52

Migration actions required

• The targets listed above continue to be available in the 5.15 branch.

Documentation

• None.
  We'll update os.mbed.com/platforms with the list of supported platforms for Mbed 6

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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

Expect regressions tests to be done by CI as part of this PR.

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Reviewers

@ARMmbed/mbed-os-maintainers

Pull request has been modified.

[evedon]

Huge clean-up. Thanks Marcelo!

[mergify]

This PR cannot be merged due to conflicts. Please rebase to resolve them.

[MarceloSalazar]

Rebased

[0xc0170]

CI started

[mbed-ci]

Test run: FAILED

Summary: 2 of 3 test jobs failed
Build number : 1
Build artifacts

Failed test jobs:

• jenkins-ci/mbed-os-ci_build-ARM
• jenkins-ci/mbed-os-ci_build-GCC_ARM

[MarceloSalazar]

I've identified and fixed an issue on the WIO_EMW3166 target for the WICED driver.
However, I can't reproduce any of the other errors. It seems there is a parameter null but I don't know where it is coming from.
@0xc0170 perhaps you could have a look?

[0xc0170]

cc @ARMmbed/mbed-os-test looks like something in CI, please review

[0xc0170]

CI restarted

[mbed-ci]

Test run: SUCCESS

Summary: 7 of 7 test jobs passed
Build number : 2
Build artifacts

[0xc0170]

Just to make sure, I'll cc here teams to be aware.

@ARMmbed/team-realtek @ThunderSoft123 @ARMmbed/team-ublox @ARMmbed/team-wiznet

I am doing final review and will merge.