drm/i915: Plug memory leak in intel_shared_dpll_start_config()

The cleanup path would reset pll->new_config to NULL but wouldn't free
the allocated memory.

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -3953,6 +3953,7 @@ static int intel_shared_dpll_start_config(struct drm_i915_private *dev_priv,
 cleanup:
 	while (--i >= 0) {
 		pll = &dev_priv->shared_dplls[i];
+		kfree(pll->new_config);
 		pll->new_config = NULL;
 	}