mmc: core: Add shutdown callback for (e)MMC bus_ops

The shutdown sequence of an (e)MMC is very similar to a suspend. We
re-use the suspend function and tell it we are not in suspend context.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: NChris Ball <cjb@laptop.org>

drivers/mmc/core/mmc.c

@@ -1508,6 +1508,14 @@ static int mmc_suspend(struct mmc_host *host)
 	return _mmc_suspend(host, true);
 }
 
+/*
+ * Shutdown callback
+ */
+static int mmc_shutdown(struct mmc_host *host)
+{
+	return _mmc_suspend(host, false);
+}
+
 /*
  * Resume callback from host.
  *
@@ -1597,6 +1605,7 @@ static const struct mmc_bus_ops mmc_ops = {
 	.resume = NULL,
 	.power_restore = mmc_power_restore,
 	.alive = mmc_alive,
+	.shutdown = mmc_shutdown,
 };
 
 static const struct mmc_bus_ops mmc_ops_unsafe = {
@@ -1608,6 +1617,7 @@ static const struct mmc_bus_ops mmc_ops_unsafe = {
 	.runtime_resume = mmc_runtime_resume,
 	.power_restore = mmc_power_restore,
 	.alive = mmc_alive,
+	.shutdown = mmc_shutdown,
 };
 
 static void mmc_attach_bus_ops(struct mmc_host *host)