qa/common.check - refactor valgrind support
qa/common.check - refactor valgrind support

Simple change to expose _filter_valgrind() that can be used with
roll-your-own valgrind execution (when _run_valgrind is not appropriate).

wuliming/pcp,adfernandes/pcp,wuliming/pcp,tjanez/pcp,andyvand/cygpcpfans,aeg-aeg/pcpfans,adfernandes/pcp,prasincs/pcp,aeg-aeg/pcpfans,adfernandes/pcp,prasincs/pcp,wuliming/pcp,adfernandes/pcp,adfernandes/pcp,tjanez/pcp,edwardt/pcp,andyvand/cygpcpfans,edwardt/pcp,adfernandes/pcp,aeg-aeg/pcpfans,adfernandes/pcp,wuliming/pcp,wuliming/pcp,wuliming/pcp,aeg-aeg/pcpfans,mbaldessari/pcp,tjanez/pcp,edwardt/pcp,andyvand/cygpcpfans,mbaldessari/pcp,andyvand/cygpcpfans,tjanez/pcp,andyvand/cygpcpfans,edwardt/pcp,adfernandes/pcp,prasincs/pcp,aeg-aeg/pcpfans,prasincs/pcp,tjanez/pcp,mbaldessari/pcp,aeg-aeg/pcpfans,edwardt/pcp,andyvand/cygpcpfans,edwardt/pcp,wuliming/pcp,mbaldessari/pcp,tjanez/pcp,prasincs/pcp,andyvand/cygpcpfans,tjanez/pcp,andyvand/cygpcpfans,aeg-aeg/pcpfans,mbaldessari/pcp,tjanez/pcp,wuliming/pcp,prasincs/pcp,aeg-aeg/pcpfans,mbaldessari/pcp,edwardt/pcp,prasincs/pcp,prasincs/pcp,edwardt/pcp