perf report: Properly handle branch count in match_chain()

perf report: Properly handle branch count in match_chain()

Some of the code paths I introduced before returned too early without
running the code to handle a node's branch count.  By refactoring
match_chain to only have one exit point, this can be remedied.

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1707691.qaJ269GSZW@agathebauer
Link: http://lkml.kernel.org/r/20171018185350.14893-2-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>