libperf: Avoid counting of nonfilterable fdarray fds

Avoid counting of struct pollfd *entries objects with
fdarray_flag__nonfilterable flag by fdarray__filter().

Nonfilterable objects are still processed if requested revents have been
signaled for them.

Signed-off-by: Alexey Budankov <[e-mail]>
Acked-by: Jiri Olsa <[e-mail]>
Acked-by: Namhyung Kim <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: http://lore.kernel.org/lkml/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/lib/api/fd/array.c

···
 			continue;
 		}
 
-		++nr;
+		if (!(fda->priv[fd].flags & fdarray_flag__nonfilterable))
+			++nr;
 	}
 
 	return nr;