Add QR code generation to sysinfo using U-Boot serial and
MAC address information, with support for both standard
and legacy payload formats.
When requested with --qr_display, show the QR code using the
most suitable backend for the running system
https://onedigi.atlassian.net/browse/DEL-9281
Signed-off-by: Francisco Gil <francisco.gilmartinez@digi.com>