systemid: Extend --foreign to reporting commands.

systemid: Extend --foreign to reporting commands.

Add --foreign to the remaining reporting and display commands plus
vgcfgbackup.
Add a NEEDS_FOREIGN_VGS flag for vgimport to always set --foreign.
If lvmetad is being used with --foreign, scan foreign VGs (currently
implemented as a full PV scan).
Handle these things centrally in lvmcmdline.c.
Also allow lvchange and vgchange -an/-aln to deactivate any foreign
LVs that happen to be active if something went wrong.
Remember to set the system ID when creating a new VG in vgsplit.