realtek: eth: rtl931x: reduce logging of special packet trap

realtek: eth: rtl931x: reduce logging of special packet trap

For packets trapped to the CPU for a special reason (not normal
forward), the RTL931x tag decoding always print a log message with level
INFO. This is not needed and just spams the log, e.g. when LLDP packets
are running through the network, each of them causes a log message.

Make that a debug message instead of an info message. We can keep it,
just change when it's printed.

Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/21844
Signed-off-by: Robert Marko <robimarko@gmail.com>