gsm 08.08: use ANSI function definition with (void)
diff --git a/src/gsm/gsm0808.c b/src/gsm/gsm0808.c
index eae1598..01221bd 100644
--- a/src/gsm/gsm0808.c
+++ b/src/gsm/gsm0808.c
@@ -363,7 +363,7 @@
 	},
 };
 
-const struct tlv_definition *gsm0808_att_tlvdef()
+const struct tlv_definition *gsm0808_att_tlvdef(void)
 {
 	return &bss_att_tlvdef;
 }