Document the modifications in 0.9.7 that will make the hw_ncipher.c

 Changes between 0.9.6h and 0.9.7  [XX xxx 2002]

  *) The hw_ncipher.c engine requires dynamic locks.  Unfortunately, it

     seems that in spite of existing for more than a year, no application

     author has done anything to provide the necessary callbacks, which

     means that this particular engine will not work properly anywhere.

     This is a very unfortunate situation which forces us, in the name

     of usability, to give the hw_ncipher.c a static lock, which is part

     of libcrypto.

     NOTE: This is for the 0.9.7 series ONLY.  This hack will never

     appear in 0.9.8 or later.  We EXPECT application authors to have

     dealt properly with this when 0.9.8 is released (unless we actually

     make such changes in the libcrypto locking code that changes will

     have to be made anyway).

     [Richard Levitte]

  *) In asn1_d2i_read_bio() repeatedly call BIO_read() until all content

     octets have been read, EOF or an error occurs. Without this change

     some truncated ASN1 structures will not produce an error.