drm/amdgpu: Remove unneeded variable 'ret' in amdgpu_device.c

Fixes coccicheck warning:

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c:1036:5-8: Unneeded variable: "ret". Return "0" on line 1079
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NMa Feng <mafeng.ma@huawei.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -1032,8 +1032,6 @@ static void amdgpu_device_check_smu_prv_buffer_size(struct amdgpu_device *adev)
  */
 static int amdgpu_device_check_arguments(struct amdgpu_device *adev)
 {
-	int ret = 0;
-
 	if (amdgpu_sched_jobs < 4) {
 		dev_warn(adev->dev, "sched jobs (%d) must be at least 4\n",
 			 amdgpu_sched_jobs);
@@ -1073,7 +1071,7 @@ static int amdgpu_device_check_arguments(struct amdgpu_device *adev)
 
 	adev->firmware.load_type = amdgpu_ucode_get_load_type(adev, amdgpu_fw_load_type);
 
-	return ret;
+	return 0;
 }
 
 /**