Fix warnings: static, include, un-initialized vairables

src/core/linux/SDL_fcitx.c

@@ -84,7 +84,8 @@ GetAppName()
     return SDL_strdup("SDL_App");
 }
 
-size_t Fcitx_GetPreeditString(SDL_DBusContext *dbus, DBusMessage *msg, char **ret) {
+static size_t
+Fcitx_GetPreeditString(SDL_DBusContext *dbus, DBusMessage *msg, char **ret) {
     char *text = NULL, *subtext;
     size_t text_bytes = 0;
     DBusMessageIter iter, array, sub;