opal-elog-parse: fix valgrind warning in opal_fru_pe_scn
opal-elog-parse: fix valgrind warning in opal_fru_pe_scn

Includes various extra sanity checks in that codepath

Signed-off-by: Cyril Bur <367d233c448abb973a0136207eb0cf446765a6f5@ozlabs.au.ibm.com>
Acked-by: Stewart Smith <ec31ab75ddf977353c8f660f92ea8b23f64aef25@linux.vnet.ibm.com>

leitao/ppc64-diag,leitao/ppc64-diag,leitao/ppc64-diag,leitao/ppc64-diag