busybox

bc: optimize bc_vec_push() usage

function                                             old     new   delta
bc_parse_pushNUM                                      87      80      -7
zbc_parse_stmt_possibly_auto                        1697    1689      -8
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(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-15)             Total: -15 bytes

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