add DSUA debug constant

Change-Id: I4a3a8189564345700ea4825983ab39a8411227f4
diff --git a/openbsc/src/gprs/sgsn_main.c b/openbsc/src/gprs/sgsn_main.c
index aef36ca..c852840 100644
--- a/openbsc/src/gprs/sgsn_main.c
+++ b/openbsc/src/gprs/sgsn_main.c
@@ -286,6 +286,11 @@
 		.description = "RAN Application Part (RANAP)",
 		.enabled = 1, .loglevel = LOGL_DEBUG,
 	},
+	[DSUA] = {
+		.name = "DSUA",
+		.description = "SCCP User Adaptation (SUA)",
+		.enabled = 1, .loglevel = LOGL_DEBUG,
+	},
 };
 
 static const struct log_info gprs_log_info = {