base

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