selftests/ipc: Remove unused variables

Delete variables "msg" and "pid" that have never been used.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: zhang jiao <[e-mail]>
Reviewed-by: Muhammad Usama Anjum <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

tools/testing/selftests/ipc/msgque.c

···
 
 int main(int argc, char **argv)
 {
-	int msg, pid, err;
+	int err;
 	struct msgque_data msgque;
 
 	if (getuid() != 0)