compsvc/pvm_exec: Support RPC binder

Bug: 190547489
Bug: 189947807
Test: [VM shell] /apex/com.android.compos/bin/compsvc \
          /system/bin/touch --rpc-binder
      [Android shell] /apex/com.android.compos/bin/pvm_exec --cid $CID \
              touch /data/local/tmp/foo
      # IPC did go through, but there is some unrelated problem in the
      # service, which can be fixed separately.

Change-Id: Ie3cdd58be1f98f8084b2b63dd325b76546bc5cf9
4 files changed