[AOA FFS Implementation] USB device aconfig flag for enabling userspace AOA based on device

These flags will be used by the USB accessory utils service to set the vendor property dynamically so that we can control the roll out of the usersapce AOA.

Bug: 407985367
Bug: 440091110

Test: Manually tested that property is set based on the aconfig flags being enabled/disabled.
Flag: android.hardware.usb.flags.enable_uaoa_p8
Flag: android.hardware.usb.flags.enable_uaoa_all_pixels_except_p8
[nkapron@google.com: whitespace, typo, and Flag: cleanup]

Change-Id: I08dd5d1d6bdfc8121bf212157bd163c67d8309da