[nrf noup] doc: extensions: kconfig: Add SoC sysbuild Kconfigs

Allows listing sysbuild Kconfigs for SoCs

Signed-off-by: Jamie McCrae <[email protected]>
(cherry picked from commit 1d73d0e)

Author: nordicjm

doc/_extensions/zephyr/kconfig/__init__.py

@@ -112,6 +112,9 @@ def kconfig_load(app: Sphinx) -> tuple[kconfiglib.Kconfig, kconfiglib.Kconfig, d
             for folder in soc_folders:
                 f.write('source "' + (Path(folder) / 'Kconfig.soc').as_posix() + '"\n')
 
+                if "nordic" in folder:
+                    f.write('osource "' + (Path(folder) / 'Kconfig.sysbuild').as_posix() + '"\n')
+
         with open(Path(td) / "soc" / "Kconfig", "w") as f:
             for folder in soc_folders:
                 f.write('osource "' + (Path(folder) / 'Kconfig').as_posix() + '"\n')