Slight rework of CH341 HAL

[psiegl]

I noticed, that the CH341 HAL could be a bit cleaned up. First, use the constructor / deconstructor of C++ to initiate/cleanup pinedio. Constructor throws error, in case not possible, which is then subsequently catched. Second, reworked the establishment of a MAC address for the CH341 HAL. The getMacAddr employs its parameter as an output. Thus, definining a similar variable that gets set upfront, it not useful for understanding the code.

[jp-bennett]

Looks good. I'll test it on my devices to confirm there's no surprises.

[jp-bennett]

This is not calculating MAC Addresses the same way as the old code. It's a surprisingly tricky thing to get this just right. I've run into similar issues.

libusb: warning [libusb_get_string_descriptor_ascii] suspicious bLength 18 for string descriptor (read 127) Serial 10000002 Serial length 8 settingsStrings length 0 MAC Address from CH341: 12f4f0efb6 settingsStrings length a MAC Address: 12f4f0efb6
vs
libusb: warning [libusb_get_string_descriptor_ascii] suspicious bLength 18 for string descriptor (read 127) Serial 10000002 *** Blank MAC Address not allowed!

Debugger shows that after the ch341 driver inits:
settingsStrings[mac_address] =
"9120F04F0EFB6"

[psiegl]

Interesting, seems my CH341 doesn't have any serial that is why I didn't see any issue during rework. With lsusb -v:

Bus 001 Device 021: ID 1a86:5512 QinHeng Electronics CH341 in EPP/MEM/I2C mode, EPP/I2C adapter
Negotiated speed: Full Speed (12Mbps)
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               1.10
  bDeviceClass          255 Vendor Specific Class
  bDeviceSubClass         0 [unknown]
  bDeviceProtocol         2 
  bMaxPacketSize0         8
  idVendor           0x1a86 QinHeng Electronics
  idProduct          0x5512 CH341 in EPP/MEM/I2C mode, EPP/I2C adapter
  bcdDevice            3.04
  iManufacturer           0 
  iProduct                2 USB UART-LPT
  iSerial                 0

[psiegl]

@jp-bennett I reverted the part, which reads the serial. Can you retry?