realtek: dsa: convert RTL83xx to new fast_age()

realtek: dsa: convert RTL83xx to new fast_age()

Make use of the new fast_age() helpers for the RTL83xx targets.
For this:

- split the existing rtldsa_83xx_fast_age() into two device
  specific functions. This removes a family_id check.
- change the callbacks in the config structures

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Link: https://github.com/openwrt/openwrt/pull/22145
Signed-off-by: Robert Marko <robimarko@gmail.com>