add Half support for multinomial on CPU (#104178)

Pull Request resolved: https://github.com/pytorch/pytorch/pull/104178
Approved by: https://github.com/jgong5, https://github.com/kulinseth, https://github.com/cpuhrsch
diff --git a/test/test_mps.py b/test/test_mps.py
index efa6daf..e6da181 100644
--- a/test/test_mps.py
+++ b/test/test_mps.py
@@ -743,7 +743,7 @@
 
         # Failures due to random output that they generate using
         # Philox engine causing mismatch with CPU results
-        'multinomial': [torch.float32],  # random results
+        'multinomial': [torch.float16, torch.float32],  # random results
         'uniform': [torch.float16, torch.float32],
         'rand_like': [torch.float16, torch.float32],
         'randint_like': [torch.float16, torch.float32, torch.int16, torch.int32, torch.int64, torch.uint8, torch.int8],