Lets be consistent in how we put spaces.

So we can either pass `--es device /dev/bus/usb/001/003`, or
`--es vendorId 0x0403 --es productId 0x6001`.

Apparently some devices have fixed length fields, are extra nulls at
the end. This makes parsing the output slightly more annoying in
termux so strip them on the java side.

Before termux-usb -l could return something like:

[
  {
    "device_name": "/dev/bus/usb/002/006",
    "device_id": 2006,
    "vendor_id": "0x316d",
    "product_id": "0x4c4b",
    "device_class": "0 - Usb class is determined on a per-interface basis",
    "device_sub_class": 0,
    "manufacturer_name": "Purism, SPC\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000",
    "device_protocol": 0,
    "product_name": "Librem Key\u0000\u0000\u0000\u0000\u0000\u0000\u0000",
    "serial_number": "00000000000000000000AB62",
    "configurations": 1,
    "descriptor_type": 0,
    "access_granted": false
  }
]

and now we remove all \u0000.