Merge branch 'bugfix/use_local_kconfiglib_v3.0' into 'release/v3.0'

Use kconfiglib from $IDF_PATH/tools/kconfig_new (v3.0)

See merge request espressif/esp-idf!6083

docs/gen-kconfig-doc.py

@@ -29,7 +29,13 @@
 
 
 import os
-import kconfiglib
+import sys
+
+try:
+    from . import kconfiglib
+except Exception:
+    sys.path.insert(0, os.path.dirname(os.path.realpath(__file__)))
+    import kconfiglib
 
 # Indentation to be used in the generated file
 INDENT = '    '