[FROJTEND] fix core.dtype.__repr__ (#2372)

`function_type` does not have a `name` field, which leads to an error
when debugging with gdb.

python/triton/language/core.py

@@ -275,7 +275,7 @@ class dtype:
         return self.name
 
     def __repr__(self):
-        return f'triton.language.{self.name}'
+        return f'triton.language.{str(self)}'
 
 
 class pointer_type(dtype):