internal/wayland: check pathname size

This avoids passing a truncated pathname to the kernel.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/wayland/wayland-client-helper.c

@@ -3,7 +3,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/socket.h>
-#include <sys/un.h>
 #include <unistd.h>
 
 #include "security-context-v1-protocol.h"