Various fixes to doxygen API generation

 * Fixed incorrect file definitions
 * Fixed accidental tag problems in ecjpake.h
 * Corrected function naming in X.509 module definition
diff --git a/include/mbedtls/sha512.h b/include/mbedtls/sha512.h
index 9462764..627694f 100644
--- a/include/mbedtls/sha512.h
+++ b/include/mbedtls/sha512.h
@@ -1,5 +1,5 @@
 /**
- * \file mbedtls_sha512.h
+ * \file sha512.h
  *
  * \brief SHA-384 and SHA-512 cryptographic hash function
  *