disp: add changes to generate display dlkm in android

Add Android make files and Kbuild files to support dlkm
for display driver. Also resolve header and config issues
to allow successful compilation of display driver.

Change-Id: I04d6233864ea54c0a808b295fbdccb83058f1fd2
Signed-off-by: Samantha Tran <samtran@codeaurora.org>
Signed-off-by: Chandan Uddaraju <chandanu@codeaurora.org>
Signed-off-by: Prabhanjan Kandula <pkandula@codeaurora.org>

rotator/sde_rotator_base.h

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
- * Copyright (c) 2015-2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2015-2021, The Linux Foundation. All rights reserved.
  */
 
 #ifndef __SDE_ROTATOR_BASE_H__
@@ -310,7 +310,14 @@ int sde_rotator_base_init(struct sde_rot_data_type **pmdata,
 
 void sde_rotator_base_destroy(struct sde_rot_data_type *data);
 
+#ifdef CONFIG_MSM_SDE_ROTATOR
 struct sde_rot_data_type *sde_rot_get_mdata(void);
+#else
+static inline struct sde_rot_data_type *sde_rot_get_mdata(void)
+{
+	return NULL;
+}
+#endif
 
 struct reg_bus_client *sde_reg_bus_vote_client_create(char *client_name);