boards: mimxrt1160_evk: enable messaging unit

Enable messaging unit support for RT1160 EVK

Signed-off-by: Daniel DeGrasse <daniel.degrasse@nxp.com>
diff --git a/boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm4.dts b/boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm4.dts
index a9f5657..1cc65b2 100644
--- a/boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm4.dts
+++ b/boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm4.dts
@@ -26,6 +26,7 @@
 		zephyr,flash-controller = &is25wp128;
 		zephyr,flash = &is25wp128;
 		nxp,m4-partition = &slot1_partition;
+		zephyr,ipc = &mailbox_b;
 	};
 
 
@@ -56,3 +57,7 @@
 &edma_lpsr0 {
 	status = "okay";
 };
+
+&mailbox_b {
+	status = "okay";
+};
diff --git a/boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm7.dts b/boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm7.dts
index a6b6465..278e0f2 100644
--- a/boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm7.dts
+++ b/boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm7.dts
@@ -24,6 +24,7 @@
 		zephyr,flash = &is25wp128;
 		zephyr,code-partition = &slot0_partition;
 		zephyr,cpu1-region = &ocram;
+		zephyr,ipc = &mailbox_a;
 	};
 
 	sdram0: memory@80000000 {
@@ -90,3 +91,7 @@
 zephyr_udc0: &usb1 {
 	status = "okay";
 };
+
+&mailbox_a {
+	status = "okay";
+};