drm/i915: Fix i915_driver_init_mmio error path

In case of the error we missed to call i915_mmio_cleanup
that matches earlier call to i915_mmio_setup.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20181011130008.24640-1-michal.wajdeczko@intel.com

drivers/gpu/drm/i915/i915_drv.c

@@ -1030,6 +1030,7 @@ static int i915_driver_init_mmio(struct drm_i915_private *dev_priv)
 
 err_uncore:
 	intel_uncore_fini(dev_priv);
+	i915_mmio_cleanup(dev_priv);
 err_bridge:
 	pci_dev_put(dev_priv->bridge_dev);