add cpu support for MMLU bench

simple_evaluate has a device option that seems to default to cuda. People with 128GB or even ~90GB+ of ram should be able to run eval on CPU.
Add auto detection for if torch is available

Signed-off-by: Charlie Doern <cdoern@redhat.com>

Author: cdoern

src/instructlab/eval/mmlu.py

@@ -6,6 +6,7 @@
 # Third Party
 from lm_eval.evaluator import simple_evaluate  # type: ignore
 from lm_eval.tasks import TaskManager  # type: ignore
+import torch
 
 # First Party
 from instructlab.eval.evaluator import Evaluator
@@ -58,6 +59,7 @@ def run(self) -> tuple:
             tasks=self.tasks,
             num_fewshot=self.few_shots,
             batch_size=self.batch_size,
+            device=("cuda" if torch.cuda.is_available() else "cpu"),
         )
 
         results = mmlu_output["results"]