udev: change action check from ACTION!="add|change" to ACTION=="remove"

udev: change action check from ACTION!="add|change" to ACTION=="remove"

For DM devices, the add/change/remove can appear as action for genuine
udev events.

However, there are more action types (bind, unbind, move, online, offline)
which never appear as actions for genuine DM udev events, but they can
still be synthesized (e.g. by writing "<action>" to "/sys/.../uevent" file
or by calling "udevadm trigger --action=<action>").

Let's also process these extra action types so that the udev-related content
is not lost completely, keeping all the symlinks and udev db entries just like
this was a synthetic udev event with "change" action.

Related to https://gitlab.com/lvmteam/lvm2/-/issues/4.