fix spelling mistake: 53-cgf_tmpfs.t
support LV name with and without volume group name

new style (setup-storage 2.x):

  disk_config lvm preserve_lazy:all always_format:1
  vg vg1 sda3,sdb3
  root  /  1024  ext4  rw,errors=remount-ro

old style (setup-storage 1.5):

  disk_config lvm preserve_lazy:all always_format:1
  vg vg1 sda3,sdb3
  vg1-root  /  1024  ext4  rw,errors=remount-ro

Setup-storage v1.5 and lower require the volume group to be present
in the logical volume's definition. A volume group and logical volume
may contain a hyphen in their name, but setup-storage up to v1.5 does
not support this. LVM internally uses '--' to escape a hyphen:

  vg-name lvname    =>  /dev/mapper/vg--name-lvname
  vgname  lv-name   =>  /dev/mapper/vgname-lv--name
  vg-name lv-name   =>  /dev/mapper/vg--name-lv--name
  vg-     lv-       =>  /dev/mapper/vg---lv--

In order to support hyphens (but avoid having to escape/de-escape them)
it's no longer required to specify the volume group name in the logical
volume's definition. (But for compatibility reasons it's still possible.)

example configuration for multiple volume groups / logical volumes:

  disk_config lvm preserve_lazy:all always_format:1

  vg vg1 sda3,sdb3
  root    /          1024    ext4    rw,errors=remount-ro
  home    /home      1024-   ext4    rw

  vg vg2 sdc
  scratch /mnt       1GB-4GB   xfs     rw