drm/i915: Fix W=1 warning for csr_load_work_fn()

drivers/gpu/drm/i915/intel_csr.c: In function ‘csr_load_work_fn’:
drivers/gpu/drm/i915/intel_csr.c:399:6: error: variable ‘ret’ set but not used [-Werror=unused-but-set-variable]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170118121808.27869-2-chris@chris-wilson.co.ukReviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>

drivers/gpu/drm/i915/intel_csr.c

@@ -396,13 +396,11 @@ static void csr_load_work_fn(struct work_struct *work)
 	struct drm_i915_private *dev_priv;
 	struct intel_csr *csr;
 	const struct firmware *fw = NULL;
-	int ret;
 
 	dev_priv = container_of(work, typeof(*dev_priv), csr.work);
 	csr = &dev_priv->csr;
 
-	ret = request_firmware(&fw, dev_priv->csr.fw_path,
-			       &dev_priv->drm.pdev->dev);
+	request_firmware(&fw, dev_priv->csr.fw_path, &dev_priv->drm.pdev->dev);
 	if (fw)
 		dev_priv->csr.dmc_payload = parse_csr_fw(dev_priv, fw);