idevicebackup2: fix building on win32
idevicebackup2: fix building on win32

kalev/libimobiledevice,upbit/libimobiledevice,upbit/libimobiledevice,upbit/libimobiledevice,kalev/libimobiledevice,kalev/libimobiledevice,Tatsh/libimobiledevice,Tatsh/libimobiledevice,patweb/libimobiledevice,patweb/libimobiledevice,libimobiledevice/libimobiledevice,Tatsh/libimobiledevice,Tatsh/libimobiledevice,libimobiledevice-win32/libimobiledevice,libimobiledevice-win32/libimobiledevice,libimobiledevice-win32/libimobiledevice,libimobiledevice-win32/libimobiledevice,patweb/libimobiledevice,libimobiledevice/libimobiledevice