On some devices enumeration fails on the 1st connect after bootup unless
android usb has already been set up for some function at least once.

Add --android-bootup-function option that can be used on such devices
to force usb-moded to program some function and then clear the function
list when usb-moded is executed during device bootup.
Signed-off-by: Simo Piiroinen <simo.piiroinen@jollamobile.com>