perf tools: Use DECLARE_BITMAP instead of an open-coded array

Use DECLARE_BITMAP instead of an open coded array for our bitmap
of featured sections.

This makes the array an unsigned long instead of a u64 but since
we use a 256 bits bitmap, the array size shouldn't vary between
different boxes.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1255795038-13751-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>