fix bug that lead to all liveconfig tests failing

src/dc_chat.rs

@@ -1307,9 +1307,7 @@ pub unsafe fn dc_get_next_media(
         }
     }
 
-    if !list.is_null() {
-        dc_array_unref(list);
-    }
+    dc_array_unref(list);
     dc_msg_unref(msg);
     ret_msg_id
 }

src/dc_receive_imf.rs

@@ -1506,12 +1506,8 @@ unsafe fn create_or_lookup_adhoc_group(
                    ret_chat_id_blocked: *mut libc::c_int,
                    chat_id: u32,
                    chat_id_blocked: i32| {
-        if !member_ids.is_null() {
-            dc_array_unref(member_ids);
-        }
-        if !chat_ids.is_null() {
-            dc_array_unref(chat_ids);
-        }
+        dc_array_unref(member_ids);
+        dc_array_unref(chat_ids);
         free(chat_ids_str as *mut libc::c_void);
         free(grpid as *mut libc::c_void);
         free(grpname as *mut libc::c_void);