- Cleaned up header documentation

diff --git a/include/polarssl/havege.h b/include/polarssl/havege.h
index 1f6daa2..6ac2039 100644
--- a/include/polarssl/havege.h
+++ b/include/polarssl/havege.h
@@ -49,7 +49,7 @@
 /**
  * \brief          HAVEGE rand function
  *
- * \param rng_st   points to an HAVEGE state
+ * \param p_rng    A HAVEGE state
  *
  * \return         A random int
  */