gad.c: fix rc for osmo_gad_enc_ell_point_unc_circle()

Related: CID#214889
Change-Id: If9bb6ab22280e0dc66ca21bba9409d817603dd4f
diff --git a/src/gsm/gad.c b/src/gsm/gad.c
index f7ee48a..23b907a 100644
--- a/src/gsm/gad.c
+++ b/src/gsm/gad.c
@@ -271,7 +271,7 @@
 	};
 	osmo_store32be_ext(osmo_gad_enc_lat(v->lat), raw->lat, 3);
 	osmo_store32be_ext(osmo_gad_enc_lon(v->lon), raw->lon, 3);
-	return sizeof(&raw);
+	return sizeof(raw);
 }
 
 static int osmo_gad_dec_ell_point_unc_circle(struct osmo_gad_ell_point_unc_circle *v,