release memory before exiting
release memory before exiting

'buf' could be freed after calling atoi, providing a gentler way to exit

Signed-off-by: Yongyue Sun <256b00e4d5276a2945b51e0bfc7fb00f18ec09dd@gmail.com>

memcached/memcached,dormando/memcached,bpzhang/memcached,guikcd/memcached,dormando/memcached,samanbarghi/memcached,elfchief/memcached,bpzhang/memcached,memcached/memcached,guikcd/memcached,dormando/memcached,elfchief/memcached,elfchief/memcached,guikcd/memcached,memcached/memcached,gencer/memcached,rmccullagh/memcached,dormando/memcached,gencer/memcached,gencer/memcached,samanbarghi/memcached,elfchief/memcached,rmccullagh/memcached,guikcd/memcached,guikcd/memcached,gencer/memcached,gencer/memcached,rmccullagh/memcached,memcached/memcached,samanbarghi/memcached,rmccullagh/memcached,dormando/memcached,rmccullagh/memcached,memcached/memcached,samanbarghi/memcached,bpzhang/memcached,elfchief/memcached,bpzhang/memcached