Only count with the extra metadata extents in new VGs and LVs (#1072999)

Existing VGs and LVs were likely created by a code that doesn't use the same
logic for counting with extra metadata for LVM on RAID.
Limit the LV size to VG's free space size

When creating the LV we should check its VG free space size and shrink the LV if
it exceeds the biggest possible size.

Related: rhbz#1072999
Use container's parent's name for PV if available (#1065737)

When modifying the PV in the LVMFactory, we want to keep its name.