pdr: optimize record handle computation
pdr: optimize record handle computation

Instead of noting the last used record handle, fetch this from the last
PDR record. This works because record handles are assigned by increments
of 1.

Signed-off-by: Deepak Kodihalli <54105a30055f1e07853b8ee7a2f0d75d22ed98c1@in.ibm.com>
Change-Id: I40fe411e1b966fad28cab6e855648b135a946678

openbmc/pldm,openbmc/pldm,openbmc/pldm