[stm32] Add upstream FreeRTOS support for stm32
This adds an upstream FreeRTOS Kernel LTS V10.4.3 and integrates it into
the stm32f439zi-nucleo build.
Using upstream FreeRTOS directly removes the depencency on ST's FreeRTOS
fork and the CMSIS-RTOS wrapper code.
Change-Id: Ia8a14a1d01a1250661441ea77af2f6b846f936ec
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/experimental/+/40360
Commit-Queue: Varun Sharma <vars@google.com>
Reviewed-by: Ali Zhang <alizhang@google.com>
diff --git a/.gitmodules b/.gitmodules
index be13cc0..93ba2bd 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -31,3 +31,6 @@
[submodule "third_party/stm32cubef4/freertos"]
path = third_party/stm32cubef4/freertos
url = https://github.com/STMicroelectronics/stm32_mw_freertos.git
+[submodule "third_party/freertos/Source"]
+ path = third_party/freertos/Source
+ url = https://github.com/FreeRTOS/FreeRTOS-Kernel.git