Some wacom w9013 devices have a vddl supply for "low valtage"
requirements. Add support in this driver to turn on this low voltage
supply. We can also drop a handful of error messages because the
regulator core is already printing an error when bulk regulators fail to
enable or disable.
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Dmitry Torokhov <dtor@chromium.org> Cc: Doug Anderson <dianders@chromium.org> Acked-by: Rob Herring <robh@kernel.org> Cc: <devicetree@vger.kernel.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>