hardware wallets: redefine "id_" for hid devices to avoid collisions

I had a ledger nano S and a ledger nano S plus connected at the same time,
and the "id_"s were colliding resulting in weird behaviour. Multisig was pretty
much not usable with both devices connected simultaneously.

Example dicts returned by `hid.enumerate(0, 0)`:

{'path': b'\\\\?\\hid#vid_2c97&pid_1015&mi_00#a&2a30{REDACTED}&0&0000#{REDACTED_UUID}', 'vendor_id': 11415, 'product_id': 4117, 'serial_number': '0001', 'release_number': 513, 'manufacturer_string': 'Ledger', 'product_string': 'Nano S', 'usage_page': 65440, 'usage': 1, 'interface_number': 0},

{'path': b'\\\\?\\hid#vid_2c97&pid_5011&mi_00#a&28d{REDACTED}&0&0000#{REDACTED_UUID}', 'vendor_id': 11415, 'product_id': 20497, 'serial_number': '0001', 'release_number': 513, 'manufacturer_string': 'Ledger', 'product_string': 'Nano S Plus', 'usage_page': 65440, 'usage': 1, 'interface_number': 0}

electrum/plugins/hw_wallet/plugin.py

@@ -66,13 +66,14 @@ class HW_PluginBase(BasePlugin):
         return self.parent.device_manager
 
     def create_device_from_hid_enumeration(self, d: dict, *, product_key) -> Optional['Device']:
+        # note: id_ needs to be unique between simultaneously connected devices,
+        #       and ideally unchanged while a device is connected.
         # Older versions of hid don't provide interface_number
         interface_number = d.get('interface_number', -1)
         usage_page = d['usage_page']
-        id_ = d['serial_number']
-        if len(id_) == 0:
-            id_ = str(d['path'])
-        id_ += str(interface_number) + str(usage_page)
+        # id_=str(d['path']) in itself might be sufficient, but this had to be touched
+        # a number of times already, so let's just go for the overkill approach:
+        id_ = f"{d['path']},{d['serial_number']},{interface_number},{usage_page}"
         device = Device(path=d['path'],
                         interface_number=interface_number,
                         id_=id_,