tests: posix: xsi_realtime: add missing includes

Add missing includes to test.

Signed-off-by: Anas Nashif <[email protected]>

Author: nashif

tests/posix/xsi_realtime/src/shm.c

@@ -9,6 +9,8 @@
 #include <zephyr/kernel.h>
 #include <zephyr/net/socket.h>
 #include <zephyr/posix/fcntl.h>
+#include <zephyr/posix/unistd.h>
+#include <zephyr/posix/sys/stat.h>
 #include <zephyr/sys/fdtable.h>
 
 #include <zephyr/ztest.h>