pmdadm: fix two dmcache metrics encoding on big-endian machines
pmdadm: fix two dmcache metrics encoding on big-endian machines

Problem detected by test qa/657.

adfernandes/pcp,tjanez/pcp,tjanez/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,prasincs/pcp,aeg-aeg/pcpfans,prasincs/pcp,adfernandes/pcp,tjanez/pcp,aeg-aeg/pcpfans,wuliming/pcp,wuliming/pcp,prasincs/pcp,adfernandes/pcp,wuliming/pcp,prasincs/pcp,prasincs/pcp,wuliming/pcp,prasincs/pcp,aeg-aeg/pcpfans,aeg-aeg/pcpfans,wuliming/pcp,tjanez/pcp,aeg-aeg/pcpfans,edwardt/pcp,prasincs/pcp,wuliming/pcp,wuliming/pcp,edwardt/pcp,edwardt/pcp,aeg-aeg/pcpfans,aeg-aeg/pcpfans,tjanez/pcp,prasincs/pcp,edwardt/pcp,wuliming/pcp,edwardt/pcp,aeg-aeg/pcpfans,adfernandes/pcp,tjanez/pcp,edwardt/pcp,edwardt/pcp,edwardt/pcp,tjanez/pcp,adfernandes/pcp,tjanez/pcp