perf symbols: Store if there is a filter in place

When setting yup the symbols library we setup several filter lists,
for dsos, comms, symbols, etc, and there is code that, if there are
filters, do certain operations, like recalculate the number of non
filtered histogram entries in the top/report TUI.

But they were considering just the "Zoom" filters, when they need to
take into account as well the above mentioned filters (perf top --comms,
--dsos, etc).

So store in symbol_conf.has_filter true if any of those filters is in
place.

Cc: Adrian Hunter <[e-mail]>
Cc: Borislav Petkov <[e-mail]>
Cc: David Ahern <[e-mail]>
Cc: Frederic Weisbecker <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Stephane Eranian <[e-mail]>
Link: http://lkml.kernel.org/n/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/symbol.c

···
 		pr_err("problems parsing %s list\n", list_name);
 		return -1;
 	}
+
+	symbol_conf.has_filter = true;
 	return 0;
 }
 

tools/perf/util/symbol.h

···
 			demangle_kernel,
 			filter_relative,
 			show_hist_headers,
-			branch_callstack;
+			branch_callstack,
+			has_filter;
 	const char	*vmlinux_name,
 			*kallsyms_name,
 			*source_prefix,