qemu-option: qemu_opts_validate(): use error_set()

net_client_init() propagates the error up by calling qerror_report_err(),
because its users expect QError semantics.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-By: Laszlo Ersek <lersek@redhat.com>
diff --git a/qemu-option.h b/qemu-option.h
index 4d5b3d3..e9fbbb5 100644
--- a/qemu-option.h
+++ b/qemu-option.h
@@ -125,7 +125,7 @@
                   const char *name, const char *value);
 const char *qemu_opts_id(QemuOpts *opts);
 void qemu_opts_del(QemuOpts *opts);
-int qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc);
+void qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp);
 int qemu_opts_do_parse(QemuOpts *opts, const char *params, const char *firstname);
 QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params, int permit_abbrev);
 void qemu_opts_set_defaults(QemuOptsList *list, const char *params,