PM: Brown-out reset level control

[parthitce]

Dose Power mode provide an API to set the brown-out reset level to the system? The zephyr Api likes: DL_SYSCTL_setBORThreshold(DL_SYSCTL_BOR_THRESHOLD_LEVEL_0);

[parthitce]

There is no direct way to express BOR in zephyr. So the best way is to handle it using HAL API's directly. Here is the reference: e9e04cf

[testo-jeff]

Verified and ok to use HAL api DL_SYSCTL_setBORThreshold.