drm/panel-simple: Use ktime_get_boottime for delays

ktime_get_boottime continues while the device is suspended. This change
ensures that the resume path will not be delayed if the power off delay
has already been met while the device is suspended
Signed-off-by: Drew Davenport <ddavenport@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221117133655.3.Iebd9f79aba0a62015fd2383fe6986c2d6fe12cfd@changeid

drivers/gpu/drm/panel/panel-simple.c

@@ -280,7 +280,7 @@ static void panel_simple_wait(ktime_t start_ktime, unsigned int min_ms)
 		return;
 
 	min_ktime = ktime_add(start_ktime, ms_to_ktime(min_ms));
-	now_ktime = ktime_get();
+	now_ktime = ktime_get_boottime();
 
 	if (ktime_before(now_ktime, min_ktime))
 		msleep(ktime_to_ms(ktime_sub(min_ktime, now_ktime)) + 1);
@@ -307,7 +307,7 @@ static int panel_simple_suspend(struct device *dev)
 
 	gpiod_set_value_cansleep(p->enable_gpio, 0);
 	regulator_disable(p->supply);
-	p->unprepared_time = ktime_get();
+	p->unprepared_time = ktime_get_boottime();
 
 	kfree(p->edid);
 	p->edid = NULL;
@@ -351,7 +351,7 @@ static int panel_simple_resume(struct device *dev)
 	if (p->desc->delay.prepare)
 		msleep(p->desc->delay.prepare);
 
-	p->prepared_time = ktime_get();
+	p->prepared_time = ktime_get_boottime();
 
 	return 0;
 }