drm/hdcp: gathering hdcp related code into drm_hdcp.c

Considering the significant size of hdcp related code in drm, all
hdcp related codes are moved into separate file called drm_hdcp.c.

v2:
  Rebased.
v2:
  Rebased.

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190507162745.25600-7-ramalingam.c@intel.com
diff --git a/include/drm/drm_hdcp.h b/include/drm/drm_hdcp.h
index 2f0335d..13771a4 100644
--- a/include/drm/drm_hdcp.h
+++ b/include/drm/drm_hdcp.h
@@ -286,7 +286,10 @@ struct hdcp_srm_header {
 } __packed;
 
 struct drm_device;
+struct drm_connector;
 
 bool drm_hdcp_check_ksvs_revoked(struct drm_device *dev,
 				 u8 *ksvs, u32 ksv_count);
+int drm_connector_attach_content_protection_property(
+		struct drm_connector *connector);
 #endif