[Misc] Remove deprecation warning (#2107)

## Purpose ##
* Remove deprecation decorator which was accidentally added to
`disable_lm_head`

Signed-off-by: Kyle Sayers <kylesayrs@gmail.com>

Author: kylesayrs

src/llmcompressor/utils/helpers.py

@@ -1093,7 +1093,6 @@ def calibration_forward_context(model: torch.nn.Module):
         yield
 
 
-@deprecated()
 @contextlib.contextmanager
 def disable_lm_head(model: torch.nn.Module):
     """