PM / runtime: Update links_count also if !CONFIG_SRCU

Commit baa8809f6097 (PM / runtime: Optimize the use of device links)
added an invocation of pm_runtime_drop_link() to __device_link_del().
However there are two variants of that function, one for CONFIG_SRCU and
another for !CONFIG_SRCU, and the commit only modified the former.

Fixes: baa8809f6097 (PM / runtime: Optimize the use of device links)
Cc: v4.10+ <stable@vger.kernel.org> # v4.10+
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/core.c

@@ -310,6 +310,9 @@ static void __device_link_del(struct device_link *link)
 	dev_info(link->consumer, "Dropping the link to %s\n",
 		 dev_name(link->supplier));
 
+	if (link->flags & DL_FLAG_PM_RUNTIME)
+		pm_runtime_drop_link(link->consumer);
+
 	list_del(&link->s_node);
 	list_del(&link->c_node);
 	device_link_free(link);