Add SoC revision, CPU part number, and a flag for engineering samples to
the rtl83xx_soc_info structure.
Also extend the system type string to include this information.
Signed-off-by: Jan Hoffmann <jan@3e8.eu>
Link: https://github.com/openwrt/openwrt/pull/19653
Signed-off-by: Robert Marko <robimarko@gmail.com>