report: add separate LVSINFOSTATUS field type for info+status combined fields

report: add separate LVSINFOSTATUS field type for info+status combined fields

Add separate LVSINFOSTATUS field type for fields which display both
dm info-like and dm status-like information.

The internal interface is there with the introduction of LVSSTATUS
field type which can cope with the combination of LVSSTATUS
and LVSINFO field types (several fields).

However, till now, we considered that *single* field can display
either LVSINFO or LVSSTATUS, but not both at the same time.

Till now, we haven't had single field which needs both - hence
add LVSINFOSTATUS field type for such fields as we currently
need this for the lv_attr field which requires combination of
info and status.

This patch just adds interface for an ability to register such fields
(the code that copes with this is already in).