perf symbols: Record the reason for filtering an address_location

By turning the addr_location->filtered member from a boolean to a u8
bitmap, reusing (and extending) the hist_filter enum for that.

This patch doesn't change the logic at all, as it keeps the meaning of
al->filtered !0 to mean that the entry _was_ filtered, so no change in
how this value is interpreted needs to be done at this point.

This will be soon used in upcoming patches.

Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-89hmfgtr9t22sky1lyg7nw7l@git.kernel.org
[ yanked this out of a previous patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>