shisa: small memleaks

[Elrond]

Hi Simon,

Just wrote my first test apps with shisa (worked good, I
got compataible arcfour-hmac hashes out of shisa).

Running it with valgrind revealed two small memleaks:

- shisa_done() should free dbh->dbs, if it is != NULL.
- shisa_cfg_db() should free "db" (suggested patch
  appended)
- I don't know, if you like "const", I do.


    Elrond

shisa_cfg_db-ml.diff
Description: Text document