Fixes to the android usb-sample apps

[balazsbanto]

• Changed mutability flag to PendingIntent.FLAG_MUTABLE (with PendingIntent.FLAG_IMMUTABLE the usb permission is not always granted. See: https://stackoverflow.com/questions/73131973/android-external-fingerprint-usb-always-returns-false-on-usb-permission and https://stackoverflow.com/questions/73267829/androidstudio-usb-extra-permission-granted-returns-false-always/
• Always request device permission before opening a device (this was not the case when “check()” function was called and the usb device was connected before launching the app)
• Remapped “OnConnectReturn” enum values since it was not handling the “0” and “3” case (AudioAndMIDISuccess) correctly.