drm/bridge: it6505: Check power state with it6505->powered in IRQ handler

On system resume, the driver might call it6505_poweron directly if the
runtime PM hasn't been enabled. In such case, pm_runtime_get_if_in_use
will always return 0 because dev->power.runtime_status stays at
RPM_SUSPENDED, and the IRQ will never be handled.

Use it6505->powered from the driver struct fixes this because it always
gets updated when it6505_poweron is called.

Fixes: 5eb9a43 ("drm/bridge: it6505: Guard bridge power in IRQ handler")
Signed-off-by: Pin-yen Lin <treapking@chromium.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230727100131.2338127-1-treapking@chromium.org

Author: Pin-yen Lin

drivers/gpu/drm/bridge/ite-it6505.c

@@ -2517,9 +2517,11 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
 	};
 	int int_status[3], i;
 
-	if (it6505->enable_drv_hold || pm_runtime_get_if_in_use(dev) <= 0)
+	if (it6505->enable_drv_hold || !it6505->powered)
 		return IRQ_HANDLED;
 
+	pm_runtime_get_sync(dev);
+
 	int_status[0] = it6505_read(it6505, INT_STATUS_01);
 	int_status[1] = it6505_read(it6505, INT_STATUS_02);
 	int_status[2] = it6505_read(it6505, INT_STATUS_03);