perf callchains: Ask for PERF_RECORD_MMAP for data mmaps for DWARF unwinding

perf callchains: Ask for PERF_RECORD_MMAP for data mmaps for DWARF unwinding

When we use a global DWARF setting as in:

	perf record --call-graph dwarf

According to d98e2b1a36ce ("perf record: Store data mmaps for dwarf unwind") we need
to set up some extra perf_event_attr bits.

But when we instead do a per event dwarf setting:

	perf record -e cycles/call-graph=dwarf/

This was not being done, make them equivalent.

This didn't produce any output changes in my tests while fixing up loose
ends in the per-event settings, I found it just by comparing the
perf_event_attr fields trying to find an explanation for those problems.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hendrick Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Noel Grandin <noelgrandin@gmail.com>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-6476r53h2o38skbs9qa4ust4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>