floss: reduce descriptor of uhid

The uhid device is created to help suspend. It does not need to be a
fully functional device.

Bug: 309017352
Bug: 330782760
Test: mma -j32
Test: suspend and check wake type
Flag: EXEMPT floss only change
Change-Id: Idd4d5da4df482a13a03aa993dca6b195aa6ed734