virpcivpd: Bring variables into loops

virpcivpd: Bring variables into loops

I've noticed one function inside virpcivpd.c, namely
virPCIVPDParseVPDLargeResourceFields() that declares some
variables at the top level even though they are used only inside
a loop in which they have to be freed explicitly.

Bringing variable declarations into the loop allows us to make
the code nicer.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Tim Wiederhake <twiederh@redhat.com>