Make gsm48_sendmsg public as well
diff --git a/src/gsm_04_08.c b/src/gsm_04_08.c
index e2cba5b..69207d7 100644
--- a/src/gsm_04_08.c
+++ b/src/gsm_04_08.c
@@ -188,7 +188,7 @@
 	return msgb_alloc_headroom(GSM48_ALLOC_SIZE, GSM48_ALLOC_HEADROOM);
 }
 
-static int gsm48_sendmsg(struct msgb *msg)
+int gsm48_sendmsg(struct msgb *msg)
 {
 	struct gsm48_hdr *gh = (struct gsm48_hdr *) msg->data;