Revert "block: mount_action: handle mount/umount deps"

Revert "block: mount_action: handle mount/umount deps"

This reverts commit 32c3126b2f0464106d74317336b6aef1d7d5f82f.

Internally stored list of devices is implemented using struct vlist_tree
and keeps devices sorted by their mount target paths. This DOESN'T mean
that all preceding entires of a given device are its parent devices.
Making such an assumption and mounting all preceding devices results in
unwanted mounts in most cases.

For example having devices like:
/dev/sda1 (mount target: /mnt/foo1)
/dev/sda2 (mount target: /mnt/foo2)
/dev/sdb1 (mount target: /mnt/bar1)
/dev/sdb2 (mount target: /mnt/bar2)
will result in devices vlist_tree having entries sorted like:
/dev/sdb1 (bar1), /dev/sdb2 (bar2), /dev/sda1 (foo1), /dev/sda2 (foo2)

Using autofs and accessing /mnt/foo2 would result in mounting all 4
partitions and spinning unneeded /dev/sdb.

Cc: Yousong Zhou <yszhou4tech@gmail.com>
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>