Virtual rotary encoder native support

 - detect rotary encoder input devices if they have a single scroll
   axis and nothing else

 - make the rotary mapper display-aware as the virtual rotary is
   constrained to a single virtual display, just like the other
   virtual input devices

Fix: 320328752
Test: atest inputflinger_tests
Test: see CTS in topic
Flag: android.companion.virtualdevice.flags.virtual_rotary

Change-Id: I5581013d06708cbcc2c3ac8a622cd259aea8a9b4