mmc: at91_mci: reorder timer setup and mmc_add_host() call

As said in function comment mmc_add_host() requires that:
"The host must be prepared to start servicing requests
before this function completes."

During this function, at91_mci_request() can be invoqued
without timer beeing setup leading to a kernel Oops.
This has been reported inserting this driver as a module.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Reported-by: Wu Xuan <wux@landicorp.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

drivers/mmc/host/at91_mci.c

@@ -1088,6 +1088,8 @@ static int __init at91_mci_probe(struct platform_device *pdev)
 		goto fail0;
 	}
 
+	setup_timer(&host->timer, at91_timeout_timer, (unsigned long)host);
+
 	platform_set_drvdata(pdev, mmc);
 
 	/*
@@ -1101,8 +1103,6 @@ static int __init at91_mci_probe(struct platform_device *pdev)
 
 	mmc_add_host(mmc);
 
-	setup_timer(&host->timer, at91_timeout_timer, (unsigned long)host);
-
 	/*
 	 * monitor card insertion/removal if we can
 	 */