display: Add rotation angle API

display: Add rotation angle API

rotation angle means "physical display" angle.
Clients can rotate display or check current display angle.

API function
-device_display_get_rotation_angle : get current display rotation angle
-device_display_set_rotation_angle : rotate physical display to set angle

Enumeration
-device_display_rotation_angle_e
	DEVICE_DISPLAY_ROTATION_ANGLE_UNKNOWN : It can be seen in laid device
	DEVICE_DISPLAY_ROTATION_ANGLE_DEGREE_0 : Initial display rotation angle
	DEVICE_DISPLAY_ROTATION_ANGLE_DEGREE_90 : 90° rotation angle
	DEVICE_DISPLAY_ROTATION_ANGLE_DEGREE_180 : 180° rotation angle
	DEVICE_DISPLAY_ROTATION_ANGLE_DEGREE_270 : 270° rotation angle
	DEVICE_DISPLAY_ROTATION_ANGLE_DEGREE_360 : 360° rotation angle

-device_display_rotation_direction_e
	DEVICE_DISPLAY_ROTATION_DIRECTION_CLOCKWISE : Rotate clockwise direction
	DEVICE_DISPLAY_ROTATION_DIRECTION_COUNTER_CLOCKWISE : Rotate counter clockwise direction

Change-Id: Iae840b217977e2540883fec31f5e2631aa93b967
Signed-off-by: TaeminYeom <taemin.yeom@samsung.com>
[cw00.choi: Add DEVICE_DISPLAY_ROTATION_ANGLE_DEGREE_360 enum]
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>