Add FreeRTOS wrapper.

[dmitrykos]

Work in progress.

[github-actions]

MemBrowse Memory Report

stm32f0-sleep

• FLASH: .text +48 B (+0.2%, 19,564 B / 65,536 B, total: 30% used)

stm32f1-sleep

• FLASH: .text +44 B (+0.2%, 18,657 B / 131,072 B, total: 14% used)

stm32f4-sleep

• FLASH: .text +40 B (+0.2%, 19,485 B / 1,048,576 B, total: 2% used)

[github-actions]

LCOV of commit cce2852 during Code Coverage - Generic #525

Summary coverage rate:
  lines......: 99.0% (1238 of 1251 lines)
  functions..: 42.7% (1571 of 3679 functions)
  branches...: no data found

Files changed coverage rate: n/a

⛔ The code coverage is too low: 98.96. Expected at least 100.

[github-actions]

LCOV of commit 4620384 during Code Coverage - Generic #526

Summary coverage rate:
  lines......: 100.0% (1253 of 1253 lines)
  functions..: 42.8% (1575 of 3679 functions)
  branches...: no data found

Files changed coverage rate: n/a

[github-actions]

LCOV of commit 53fe69d during Code Coverage - Generic #527

Summary coverage rate:
  lines......: 100.0% (1253 of 1253 lines)
  functions..: 42.8% (1575 of 3679 functions)
  branches...: no data found

Files changed coverage rate: n/a