cont : fix supports_op for ARGMAX

Author: ggerganov

ggml/src/ggml-metal/ggml-metal.m

@@ -1982,7 +1982,7 @@ static bool ggml_metal_supports_op(const struct ggml_backend_metal_device_contex
         case GGML_OP_L2_NORM:
             return has_simdgroup_reduction && (op->ne[0] % 4 == 0 && ggml_is_contiguous_1(op->src[0]));
         case GGML_OP_ARGMAX:
-            return true;
+            return has_simdgroup_reduction;
         case GGML_OP_NORM:
             return has_simdgroup_reduction && (op->ne[0] % 4 == 0 && ggml_is_contiguous_1(op->src[0]));
         case GGML_OP_ROPE: