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_icp/cam_icp_subdev.h

@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2019, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _CAM_ICP_SUBDEV_H_
+#define _CAM_ICP_SUBDEV_H_
+
+/**
+ * @brief : API to register ICP subdev to platform framework.
+ * @return struct platform_device pointer on on success, or ERR_PTR() on error.
+ */
+int cam_icp_init_module(void);
+
+/**
+ * @brief : API to remove ICP subdev from platform framework.
+ */
+void cam_icp_exit_module(void);
+
+#endif /* _CAM_ICP_SUBDEV_H_ */