New, lighter hashing functions: Ascon-Hasha and Ascon-XOFa, as per Ascon's NIST submission update (2021). Pre-initialised hashes.

Added

• Ascon-Hasha functions:

  • Offline processing:
    • ascon_hasha()
    • ascon_hasha_matches()
  • Online processing:
    • ascon_hasha_init()
    • ascon_hasha_update()
    • ascon_hasha_final()
    • ascon_hasha_final_matches()

• Ascon-XOFa functions:

  • Offline processing:
    • ascon_hasha_xof()
    • ascon_hasha_xof_matches()
  • Online processing:
    • ascon_hasha_xof_init()
    • ascon_hasha_xof_update()
    • ascon_hasha_xof_final()
    • ascon_hasha_xof_final_matches()

Fixed

• Faster initialisation phase of all hashing functions states: using
  precomputed sponges for each hashing function instead of applying its
  initialisation vector and permuting it with 12 rounds. Given that this
  operation is deterministic, we can trade code size space (the precomputed
  sponges) for computation time (no permutation needed).
• Add struct names to anonymous structs that were only typedef-ed in the
  library header. Helps when debugging, so the debugger can show the struct
  name.
• Minor internal simplifications of the benchmark and test suite.