Support identifying usb midi device using usb sysfs

Out-of-tree ACK patches previously enabled MIDI device identification
via the "/sys/class/android_usb/android0/f_midi/alsa" sysfs node.
This change introduces a new, upstream-compliant method for MIDI
device identification. This method requires the upstream patch [1]
within the underlying ACK.

[1] https://patchwork.kernel.org/project/linux-usb/patch/20240307030922.3573161-1-royluo@google.com/

Flag: android.hardware.usb.flags.enable_usb_sysfs_midi_identification
Bug: 333778731
Test: exercise usb midi with the flag on/off
Change-Id: I64635f083541bfc59bfa4857d0fc5f20a5f3c2f5