LVM/DM rules in dracut

LVM/DM rules in dracut

I've looked at the LVM rules used in dracut just recently
and it needs fixing - we should react to change events only
for DM devices, so we have to skip vol_id/blkid call on ADD:

KERNEL=="dm-[0-9]*", ACTION=="add", GOTO="lvm_end"

Also, MD devices have their own rules, where vol_id/blkid
is called and where the symlinks are created (when looking
into raw initrd, this is in  64-md-raid.rules).

Also, if those rules are meant to be for DM devices only,
maybe we should skip symlink creation for the other devices
there, to keep the rules clean and straightforward. I think
we shouldn't create/recreate symlinks for non-dm devices in
LVM/DM rules (..should be in appropriate rules for that type
of device):

KERNEL!="dm-[0-9]*", GOTO="lvm_end"