drm/i915/display: Mark conn as initialised by iterator

smatch complains about
drivers/gpu/drm/i915//display/intel_display.c:14403 intel_set_dp_tp_ctl_normal() error: uninitialized symbol 'conn'.
because it has no way to determine that the loop must have an entry.
Tell the static analysers to ignore the local, it will always be set.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191028142652.1987-2-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/display/intel_display.c

@@ -14391,8 +14391,8 @@ static void intel_crtc_enable_trans_port_sync(struct intel_crtc *crtc,
 static void intel_set_dp_tp_ctl_normal(struct intel_crtc *crtc,
 				       struct intel_atomic_state *state)
 {
+	struct drm_connector *uninitialized_var(conn);
 	struct drm_connector_state *conn_state;
-	struct drm_connector *conn;
 	struct intel_dp *intel_dp;
 	int i;