board/BuR/common: split br_resetc_bmode function

Split br_resetc_bmode function to add support for reading of reset
reason in board code with br_resetc_bmode_get.

Signed-off-by: Bernhard Messerklinger <bernhard.messerklinger@br-automation.com>
Link: https://lore.kernel.org/r/20250404072819.69642-4-bernhard.messerklinger@br-automation.com
Signed-off-by: Michal Simek <michal.simek@amd.com>
2 files changed