hush: use mempcpy where useful

function                                             old     new   delta
o_addblock                                            58      42     -16
expand_one_var                                      1618    1555     -63
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(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-79)             Total: -79 bytes

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