arvshowdevices: extra check for returned device id before sending it to printf.
arvshowdevices: extra check for returned device id before sending it to printf.

lu-zero/aravis,lu-zero/aravis,AravisProject/aravis,AnilRamachandran/aravis,AnilRamachandran/aravis,AravisProject/aravis,AravisProject/aravis,AnilRamachandran/aravis,lu-zero/aravis,AravisProject/aravis,AravisProject/aravis,lu-zero/aravis,AnilRamachandran/aravis,lu-zero/aravis,AnilRamachandran/aravis