samd/boards: Add two SparkFun SAMD21 boards.

[robert-hh]

Summary

Add support for the boards:

• SparkFun SAMD21 Dev Breakout
• SparkFun RedBoard Turbo

Both boards are SAMD21 based and actively sold by SparkFun.

Testing

Built the board firmware and tested it on the board.

Trade-offs and Alternatives

These are "just another" two SAMD boards. The SparkFun SAMD21 Dev Breakout works as well with the Generic SAMD21x18 firmware. Only the board Pin labels are then not supported.

[github-actions]

Code size report:

   bare-arm:    +0 +0.000% 
minimal x86:    +0 +0.000% 
   unix x64:    +0 +0.000% standard
      stm32:    +0 +0.000% PYBV10
     mimxrt:    +0 +0.000% TEENSY40
        rp2:    +0 +0.000% RPI_PICO_W
       samd:    +0 +0.000% ADAFRUIT_ITSYBITSY_M4_EXPRESS
  qemu rv32:    +0 +0.000% VIRT_RV32

[dpgeorge]

Thanks for this. I tested that both boards build, but did not run the firmware (I don't have the hardware).

[robert-hh]

Thank you for merging. I tested it with both boards.

[sfe-SparkFro]

Thanks for adding these!

FYI these boards use the wrong capitalization (Sparkfun instead of SparkFun), meaning there's now 2 different "sparkfun" vendors on the MicroPython download page:

If a user selects one, they don't see the rest of the boards (there are currently 11 other SparkFun boards):

Should an issue be made for this?

[robert-hh]

There was a PR #17258 by @malcolm-sparkfun, which was approved and merged. it changed "Sparkfun" into "SparkFun".

[dpgeorge]

That PR did not fix these two boards, so we will need a PR to fix them.

[robert-hh]

Created.