The dsa probing currently disable multiple spanning tree for RTL93xx
and keeps the bootloader setup for RTL83xx untouched. Additionally it
does this by checking for the family id. Refactor this to a common
"disable msti" setup.
To make it clear: From now on RTL83xx will also run in MSTI disabled
state. Tested on Linksys LGS310C.
Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Link: https://github.com/openwrt/openwrt/pull/22749
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>