hwrng: exynos - Use pm_runtime_resume_and_get() to replace open coding

use pm_runtime_resume_and_get() to replace pm_runtime_get_sync and
pm_runtime_put_noidle. this change is just to simplify the code, no
actual functional changes.
Signed-off-by: NTian Tao <tiantao6@hisilicon.com>
Reviewed-by: NKrzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: NŁukasz Stelmach <l.stelmach@samsung.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/exynos-trng.c

@@ -196,10 +196,9 @@ static int __maybe_unused exynos_trng_resume(struct device *dev)
 {
 	int ret;
 
-	ret = pm_runtime_get_sync(dev);
+	ret = pm_runtime_resume_and_get(dev);
 	if (ret < 0) {
 		dev_err(dev, "Could not get runtime PM.\n");
-		pm_runtime_put_noidle(dev);
 		return ret;
 	}