perf hists: Move the dso and thread filters from hist_browser

perf hists: Move the dso and thread filters from hist_browser

Since with dynamic addition of new hist entries we need to apply those
filters as we merge new batches of hist_entry instances, for instance in
perf top.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-zjhhf8kh9w1buty9p10od6rz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>