PM / Domains: Mark "name" const in dev_pm_domain_attach_by_name()

As of the patch ("PM / Domains: Mark "name" const in
genpd_dev_pm_attach_by_name()") it's clear that the name in
dev_pm_domain_attach_by_name() can be const.  Mark it as so.  This
allows drivers to pass in a name that was declared "const" in a
driver.

Fixes: 27dceb81f4 ("PM / Domains: Introduce dev_pm_domain_attach_by_name()")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/power/common.c

@@ -160,7 +160,7 @@ EXPORT_SYMBOL_GPL(dev_pm_domain_attach_by_id);
  * For a detailed function description, see dev_pm_domain_attach_by_id().
  */
 struct device *dev_pm_domain_attach_by_name(struct device *dev,
-					    char *name)
+					    const char *name)
 {
 	if (dev->pm_domain)
 		return ERR_PTR(-EEXIST);