When used with FreeRTOS, lower the interrupt priority for OTG_FS_IRQn

[kapacuk]

None of the FreeRTOS examples currently work with STM32F4, they all trigger this assert in lib/FreeRTOS-Kernel/portable/GCC/ARM_CM4F/port.c:

764 configASSERT( ucCurrentPriority >= ucMaxSysCallPriority );

because the interrupt priority for OTG_FS is too high (that is, the value of ucCurrentPriority is too low).

The (almost) correct call to NVIC_SetPriority was commented out in hw/bsp/stm32f4/family.c.

I have a suspicion that other Cortex-M chips might be affected too, but I can only test Seeeduino Xiao and STM32F4 blackpill.

[hathach]

Thank for the fix, yeah, this is very common issue when using cortex m with freertos. I have this nvic setprio for most of family, but apparently not all of them. This is downside of having too many boards/ports, that sometime I couldn't do all the hand-on testing on actual hardware

Note: The issue is only occurred if default priority (on reset) of USB is too high, somehow my stmf411disco board work just fine without this patch.