binderRpcBenchmark: repeatBinder kernel binder

Before, this was only running rpc binder for the repeateBinder test
case.

BM_repeatBinder/0                              61680 ns        33016 ns
17730
BM_repeatBinder/1                             162368 ns        87825 ns
9997

So, RPC is much slower. Investigation to come. May be related to
b/182939933 (reading /dev/urandom to come up with addresses for new RPC
binder objects).

Bug: 182940634
Test: binderRpcBenchmark
Change-Id: I02c147bb011994ab9acb9f30de00538f04cfb0d9