ssize_t is declared there (needed with embedded libc)

diff -p -up ./libkmod/libkmod-array.h.tv ./libkmod/libkmod-array.h
--- ./libkmod/libkmod-array.h.tv	2012-01-12 22:01:07.460368765 +0100
+++ ./libkmod/libkmod-array.h	2012-01-12 22:01:30.401284437 +0100
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <stddef.h>
 /*
  * Declaration of struct array is in header because we may want to embed the
  * structure into another, so we need to know its size