[rpc] fix closure problem
[rpc] fix closure problem

need to pass allocated struct to go routine as parameter or will get
last value of (s,listen) replicated N times. i.e. all go routines
share the same variables.  Pass allocated struct as parameter will
cause each go routine to get its own allocation.

Signed-off-by: Christopher Hall <97c3bc3fef1a71b149f1095f758464e4b18eb35b@bitmark.com>

bitmark-inc/bitmarkd,bitmark-inc/bitmarkd