12639 n2piupc: smatch and NULL pointer errors
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Approved by: Gordon Ross <gordon.w.ross@gmail.com>

6507462 N2 PIU bit error performance counters should be enabled at attach time

FWARC/2006/498 N2 PIU Performance Counters HV API
FWARC/2006/592 Niagara2 PIU Performance Counter bus binding and MD description
6466249 Need support for N2 PIU performance counters