Add riscv64 arch

[shanduur]

Description

New Tier 3 platform: riscv64 architecture is now included, allowing the collector to be built and distributed for this platform.

Link to tracking issue

Fixes #13462
X-Ref: open-telemetry/opentelemetry-collector-releases#969

Testing

I’ve performed basic compilation as well as starting collector inside a linux/riscv64 container (docker.io/riscv64/debian).

Documentation

Added myself as a contact point to platform-support.md document.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.41%. Comparing base (51bff5f) to head (835cfaf).
Report is 6 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #13458   +/-   ##
=======================================
  Coverage   91.41%   91.41%           
=======================================
  Files         532      532           
  Lines       29537    29537           
=======================================
  Hits        27002    27002           
  Misses       2003     2003           
  Partials      532      532           

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[atoulme]

Please add a changelog - run make chlog-new in the root of the checkout and fill the information in the file added.

[shanduur]

Do I need to reconfigure cspell? There's a lot of errors reported by it.

[mx-psi]

Do I need to reconfigure cspell? There's a lot of errors reported by it.

That's an error on main, no worries, you don't need to be the one fixing that