perf annotate: Create a annotate2 flag in struct symbol

We often use the symbol__annotate2() to annotate a specified symbol.
While annotating may take some time, so in order to avoid annotating the
same symbol repeatedly, the patch creates a new flag to indicate the
symbol has been annotated.

Signed-off-by: Jin Yao <[e-mail]>
Reviewed-by: Ingo Molnar <[e-mail]>
Reviewed-by: Jiri Olsa <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Andi Kleen <[e-mail]>
Cc: Kan Liang <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/annotate.c

···
 	notes->nr_events = nr_pcnt;
 
 	annotation__update_column_widths(notes);
+	sym->annotate2 = true;
 
 	return 0;
 

tools/perf/util/symbol.h

···
 	u8		ignore:1;
 	u8		inlined:1;
 	u8		arch_sym;
+	bool		annotate2;
 	char		name[0];
 };