busybox

sha1: use Rob's code, it's smaller and faster

function                                             old     new   delta
static.rconsts                                         -      16     +16
sha1_process_block64                                 460     298    -162
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(add/remove: 1/0 grow/shrink: 0/1 up/down: 16/-162)          Total: -146 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>