distinction (which does not work well because if CRYPTO_MDEBUG is
defined at library compile time, it is not necessarily defined at
application compile time; and memory debugging now can be reconfigured
at run-time anyway). To get the intended semantics, we could just use
the EVP_DigestInit_dbg unconditionally (which uses the caller's
__FILE__ and __LINE__ for memory leak debugging), but this would make
memory debugging inconsistent. Instead, callers can use
CRYPTO_push_info() to track down memory leaks.
Also fix indentation, and add OpenSSL copyright.