floss: Set phys attribute for uhid device

Set the phys attribute of the uhid device to the address of the
controller that created it. This allows support for multiple controllers
and is required for suspend on ChromeOS.

Bug: 230604670
Test: Connect LE keyboard and use it to wake from suspend
Tag: #floss
Change-Id: I5a14cb33316e7a063f37244e6f0437e347b642cb