[ot] python/qemu: cfggen.py: Fix unbound local in error case

Signed-off-by: Alex Jones <[email protected]>

Author: AlexJones0

python/qemu/ot/otp/const.py

@@ -241,7 +241,7 @@ def get_scrambling_key(self, name: str) -> str:
         except KeyError as exc:
             raise ValueError('No scrambling key constants found') from exc
         if len(key_values) <= idx:
-            raise ValueError(f'No such key {name} in the key array') from exc
+            raise ValueError(f'No such key {name} in the key array')
         return key_values[idx]
 
     def get_partition_inv_defaults(self, partition: int) -> Optional[str]: