gsm0480: Move the USSD parsing code to libosmocore

- Change u_int8 to uint8
- Change DEBUGP to LOGP
- Change fprintf(stderr, to LOGP(0, LOGL_DEBUG
- We should define log areas used inside libosmocore
diff --git a/include/osmocore/gsm0480.h b/include/osmocore/gsm0480.h
index 52592f7..ae92c1f 100644
--- a/include/osmocore/gsm0480.h
+++ b/include/osmocore/gsm0480.h
@@ -3,6 +3,17 @@
 
 #include "msgb.h"
 
+#define MAX_LEN_USSD_STRING	31
+
+struct ussd_request {
+	char text[MAX_LEN_USSD_STRING + 1];
+	uint8_t transaction_id;
+	uint8_t invoke_id;
+};
+
+int gsm0480_decode_ussd_request(const struct msgb *msg,
+				struct ussd_request *request);
+
 struct msgb *gsm0480_create_unstructuredSS_Notify(int alertPattern, const char *text);
 struct msgb *gsm0480_create_notifySS(const char *text);