Use async polling for HPD action

Since Device polling holds whole IO thread while it's running,
other sending requests would be blocked until it's finished.
Usually polling takes more than 1 seconds and some action might
be timeouted.
This change sends polling message asynchrousely for
each device address.

Bug: 17381548

Change-Id: I2f47931c5882649d6ac56092986d34d1da48f710