i915: Don't whine when pci_enable_msi() fails.

This probably just means the chipset doesn't support MSI, which is fine.
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/gpu/drm/i915/i915_dma.c

@@ -852,8 +852,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	 * be lost or delayed
 	 */
 	if (!IS_I945G(dev) && !IS_I945GM(dev) && !IS_I965GM(dev))
-		if (pci_enable_msi(dev->pdev))
-			DRM_ERROR("failed to enable MSI\n");
+		pci_enable_msi(dev->pdev);
 
 	intel_opregion_init(dev);