add board swm181

[iplayfast]

• Development Platform or Board.
  All issues (building, uploading, adding new boards, etc.) related to PlatformIO development platforms
  should be reported to appropriate repository related to your hardware
  https://github.com/topics/platformio-platform

I've found an inexpensive development board SWM181CBT6 that looks quite capable. But after receiving it I realized that it isn't (yet) supported by platformIO, and I frankly can't stand the stm32cube. The package is based on ARM-Cortex-MD
https://www.aliexpress.com/item/1005004702805432.html?spm=a2g0o.order_list.order_list_main.16.7cfc1802NQi3zV

I've located an stm32cube pack if that is helpful. (I couldn't figure out how to install it into the cube). The extension was originally pack, but I renamed it to zip intorder to add it here. (it actually is a zip file so it's all good).

20220721163533324_Synwit.SWM32_DFP.1.20.3.zip