hwspinlock: sprd: use module_platform_driver() instead postcore initcall

The hardware spinlock devices are defined in the DT, there's no need for
init calls order, remove boilerplate code by using module_platform_driver.

Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20201030034654.15775-3-zhang.lyra@gmail.com
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/hwspinlock/sprd_hwspinlock.c

@@ -149,18 +149,7 @@ static struct platform_driver sprd_hwspinlock_driver = {
 		.of_match_table = of_match_ptr(sprd_hwspinlock_of_match),
 	},
 };
-
-static int __init sprd_hwspinlock_init(void)
-{
-	return platform_driver_register(&sprd_hwspinlock_driver);
-}
-postcore_initcall(sprd_hwspinlock_init);
-
-static void __exit sprd_hwspinlock_exit(void)
-{
-	platform_driver_unregister(&sprd_hwspinlock_driver);
-}
-module_exit(sprd_hwspinlock_exit);
+module_platform_driver(sprd_hwspinlock_driver);
 
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");