perf annotate: Introduce strerror for handling symbol__disassemble() errors

We were just using pr_error() which makes it difficult for non stdio UIs
to provide errors using its widgets, as they need to somehow catch what
was passed to pr_error().

Fix it by introducing a __strerror() interface like the ones used
elsewhere, for instance target__strerror().

This is just the initial step, more work will be done, but first some
error handling bugs noticed while working on this need to be dealt with.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-dgd22zl2xg7x4vcnoa83jxfb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 823dbbb..418ed94 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -132,6 +132,10 @@
 	if (err == 0) {
 out_assign:
 		top->sym_filter_entry = he;
+	} else {
+		char msg[BUFSIZ];
+		symbol__strerror_disassemble(sym, map, err, msg, sizeof(msg));
+		pr_err("Couldn't annotate %s: %s\n", sym->name, msg);
 	}
 
 	pthread_mutex_unlock(&notes->lock);