Added md_process() to MD layer for generic internal access to hash
process functions

Access to process functions is needed to reduce possible timing attacks
on SSL MAC checks. As SSL is set to move to using the dynamic MD layer,
the MD layer needs access to these process functions as well.
diff --git a/library/md2.c b/library/md2.c
index 954aa07..73abdfa 100644
--- a/library/md2.c
+++ b/library/md2.c
@@ -80,7 +80,7 @@
     ctx->left = 0;
 }
 
-static void md2_process( md2_context *ctx )
+void md2_process( md2_context *ctx )
 {
     int i, j;
     unsigned char t = 0;