nvmem: mediatek: Fix later provider initialization

Possibly, provider driver initialization is later than
consumer driver. Use function subsys_initcall to initialize
NVMEM provider early to ensure NVMEM consumer doesn't need
to -EPROBE_DEFER.

Signed-off-by: Andrew-CT Chen <[e-mail]>
Signed-off-by: Srinivas Kandagatla <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/nvmem/mtk-efuse.c

···
 		.of_match_table = mtk_efuse_of_match,
 	},
 };
-module_platform_driver(mtk_efuse_driver);
+
+static int __init mtk_efuse_init(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&mtk_efuse_driver);
+	if (ret) {
+		pr_err("Failed to register efuse driver\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static void __exit mtk_efuse_exit(void)
+{
+	return platform_driver_unregister(&mtk_efuse_driver);
+}
+
+subsys_initcall(mtk_efuse_init);
+module_exit(mtk_efuse_exit);
+
 MODULE_AUTHOR("Andrew-CT Chen <[e-mail]>");
 MODULE_DESCRIPTION("Mediatek EFUSE driver");
 MODULE_LICENSE("GPL v2");