Fix messaging-method value in SP manifest

Change messaging-method from the incorrect value of 0 to 3 to
properly indicate that SPs only support sending and receiving direct
messages.

Signed-off-by: Imre Kis <imre.kis@arm.com>
Change-Id: I625e5a2dff1638132cd2121863a4c818fc561e91
diff --git a/deployments/attestation/sp/default_attestation.dts.in b/deployments/attestation/sp/default_attestation.dts.in
index e32e2e4..ef26e0e 100644
--- a/deployments/attestation/sp/default_attestation.dts.in
+++ b/deployments/attestation/sp/default_attestation.dts.in
@@ -15,7 +15,7 @@
 	exception-level = <1>; /* S-EL0 */
 	execution-state = <0>; /* AArch64 */
 	xlat-granule = <0>; /* 4KiB */
-	messaging-method = <0>; /* Direct messaging only */
+	messaging-method = <3>; /* Direct messaging only */
 
 	boot-params {
 		compatible = "arm,ffa-manifest-boot-params";