perf callchain: Fix double mapping al->addr for children without self period

perf callchain: Fix double mapping al->addr for children without self period

Milian Wolff found a problem he described in [1] and that for him would
get fixed:

"Note how most of the large offset values are now gone. Most notably, we
get proper srcline resolution for the random.h and complex headers."

Then Namhyung found the root cause:

"I looked into it and found a bug handling cumulative (children)
entries.  For children entries that have no self period, the al->addr (so
he->ip) ends up having an doubly-mapped address.

It seems to be there from the beginning but only affects entries that
have no srclines - finding srcline itself is done using a different
address but it will show the invalid address if no srcline was found.  I
think we should fix the commit c7405d85d7a3 ("perf tools: Update cpumode
for each cumulative entry")."

[1] https://lkml.kernel.org/r/20171018185350.14893-7-milian.wolff@kdab.com

Reported-by: Milian Wolff <milian.wolff@kdab.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: kernel-team@lge.com
Fixes: c7405d85d7a3 ("perf tools: Update cpumode for each cumulative entry")
Link: https://lkml.kernel.org/r/20171020051533.GA2746@sejong
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>