Update condition in _try_parse_stringlist check to explicitly compare against None

Signed-off-by: Cong Wang <cwang@multikernel.io>

Author: congwang-mk

src/kerf/dtc/parser.py

@@ -1481,7 +1481,7 @@ def _property_to_dts(self, name: str, data: bytes, indent: str) -> str:
 
         # Try parsing as stringlist
         strings = self._try_parse_stringlist(data)
-        if strings:
+        if strings is not None:
             quoted = ', '.join(f'"{s}"' for s in strings)
             return f'{indent}{name} = {quoted};'