powerpc/sysdev: Use module_platform_driver macro

This patch removes some code duplication by using
module_platform_driver.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/sysdev/pmi.c b/arch/powerpc/sysdev/pmi.c
index 8f04654..5aaf86c 100644
--- a/arch/powerpc/sysdev/pmi.c
+++ b/arch/powerpc/sysdev/pmi.c
@@ -214,18 +214,7 @@
 		.of_match_table = pmi_match,
 	},
 };
-
-static int __init pmi_module_init(void)
-{
-	return platform_driver_register(&pmi_of_platform_driver);
-}
-module_init(pmi_module_init);
-
-static void __exit pmi_module_exit(void)
-{
-	platform_driver_unregister(&pmi_of_platform_driver);
-}
-module_exit(pmi_module_exit);
+module_platform_driver(pmi_of_platform_driver);
 
 int pmi_send_message(pmi_message_t msg)
 {