We have incorporated changes based on Daniel's proposed patch into PCP.
As of commit e7406b4 in the github PCP tree on 28 Oct 2017, we're making arch independent packages for dpkg builds.
$ dpkg-query -W -f '${Package} ${Architecture}\n' pcp\* | grep all
pcp-doc all
pcp-import-ganglia2pcp all
pcp-import-iostat2pcp all
pcp-import-mrtg2pcp all
pcp-import-sar2pcp all
pcp-import-sheet2pcp all
So I think this bug can be closed.
