msm: camera: common: Make platform register centralized

Currently camera modules platform registration/remove function
is being called as a part of module_init function individually.
Building camera as module, current infrastructure cannot support
it, as DLKM only support single module_init/exit function.
This change enables that support by combining all platform
entry/remove functions centrally. Also, remove all submodule
makefiles and combined into one root makefile in order to generate
single kernel object file to dynamically loading the kernel module
in case of DLKM compilation.

CRs-Fixed: 2569808
Change-Id: I59db3ed6cef60123e474db2f222c39836056bd6e
Signed-off-by: Jigarkumar Zala <jzala@codeaurora.org>
Signed-off-by: Karthik Jayakumar <kjayakum@codeaurora.org>

drivers/cam_sync/cam_sync.c

@@ -1128,10 +1128,9 @@ static struct platform_driver cam_sync_driver = {
 	},
 };
 
-static int __init cam_sync_init(void)
+int cam_sync_init(void)
 {
 	int rc;
-
 	rc = platform_device_register(&cam_sync_device);
 	if (rc)
 		return -ENODEV;
@@ -1139,7 +1138,7 @@ static int __init cam_sync_init(void)
 	return platform_driver_register(&cam_sync_driver);
 }
 
-static void __exit cam_sync_exit(void)
+void cam_sync_exit(void)
 {
 	int idx;
 
@@ -1150,7 +1149,5 @@ static void __exit cam_sync_exit(void)
 	kfree(sync_dev);
 }
 
-module_init(cam_sync_init);
-module_exit(cam_sync_exit);
 MODULE_DESCRIPTION("Camera sync driver");
 MODULE_LICENSE("GPL v2");