[fix] Correct the returned value of has_spec_drafter (#6178)

Signed-off-by: ziyixiong-nv <[email protected]>

Author: ziyixiong-nv

tensorrt_llm/_torch/speculative/interface.py

@@ -77,7 +77,8 @@ def has_spec_decoder(self):
         return self.is_mtp() or self.is_eagle3() or self.is_eagle3_one_model()
 
     def has_spec_drafter(self):
-        return self.is_ngram() or self.is_user_provided()
+        return self.is_eagle3() or self.is_draft_target() or self.is_ngram(
+        ) or self.is_user_provided()
 
     def extend_ctx(self, attention_backend: Type[AttentionBackend]):
         """