sha: fix thinko in sha512; add FAST_FUNC to sha1/sha256

function                                             old     new   delta
sha512_process_block128                             1334    1336      +2
sha1_hash                                            112     111      -1
sha256_process_block64                               446     440      -6
sha1_process_block64                                 494     484     -10
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(add/remove: 0/0 grow/shrink: 1/3 up/down: 2/-17)             Total: -15 bytes

2 files changed