output GPIO issue with LORA_L151CCU6

[BuBuaBu]

I found the issue of gpio refusing to reset after a set. (with stm32l151xc variant)

The issue and its cause is explain in the st community forum: https://community.st.com/s/question/0D50X0000AldbDt/bug-in-stm32l151-and-others-driver-code-these-chips-dont-have-a-brr-register

That means we need to have the STM32Cube driver fixed.

There is nothing wrong with not the board definition nor the stm32duino core.

As a workaround, I set a #undef GPIO_BRR_BR_0 inside variant.h . Of course it's only to proove that this is the issue.

Do you plan to open a PR to upstream these board definitions?