xtensa: wire up statx system call

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

arch/xtensa/include/uapi/asm/unistd.h

@@ -774,7 +774,10 @@ __SYSCALL(349, sys_pkey_alloc, 2)
 #define __NR_pkey_free				350
 __SYSCALL(350, sys_pkey_free, 1)
 
-#define __NR_syscall_count			351
+#define __NR_statx				351
+__SYSCALL(351, sys_statx, 5)
+
+#define __NR_syscall_count			352
 
 /*
  * sysxtensa syscall handler