binder: host service manager limits max outgoing threads

... for each returned binder object. By default, the limit
is SIZE_MAX.

Test: aservice
  ... with max outgoing threads = 1, `aservice list` takes 19s.
  ... with max outgoing threads = SIZE_MAX, `aservice list` takes 30s.

Test: binderHostDeviceTest
Fixes: 194225767
Change-Id: Ib51fa41970fff804f40b7604a6a195ce0b16f89d