plat: imx8m: Keep A53 PLAT on in wait mode(ret)

Keep A53 PLAT(SCU) power domain on in wait mode(ret).
RBC count only need to be set in PLAT OFF mode, so
change it accordingly.

Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Change-Id: Ie55e25c8210d298506fc4dca7a9653583db45e0c
diff --git a/plat/imx/imx8m/imx8m_psci_common.c b/plat/imx/imx8m/imx8m_psci_common.c
index d641628..dbb772d 100644
--- a/plat/imx/imx8m/imx8m_psci_common.c
+++ b/plat/imx/imx8m/imx8m_psci_common.c
@@ -192,7 +192,7 @@
 	 * drived by the 32K OSC, so delay 30us to make sure the counter
 	 * is really running.
 	 */
-	if (!is_local_state_run(CLUSTER_PWR_STATE(target_state))) {
+	if (is_local_state_off(CLUSTER_PWR_STATE(target_state))) {
 		imx_set_rbc_count();
 		udelay(30);
 	}