GUAC-1164: Conditionally build display update channel support.

src/protocols/rdp/rdp_disp.c

@@ -27,10 +27,13 @@
 #include "rdp_settings.h"
 
 #include <freerdp/freerdp.h>
-#include <freerdp/client/disp.h>
 #include <guacamole/client.h>
 #include <guacamole/timestamp.h>
 
+#ifdef HAVE_FREERDP_CLIENT_DISP_H
+#include <freerdp/client/disp.h>
+#endif
+
 guac_rdp_disp* guac_rdp_disp_alloc() {
 
     guac_rdp_disp* disp = malloc(sizeof(guac_rdp_disp));

src/protocols/rdp/rdp_disp.h

@@ -25,9 +25,12 @@
 
 #include "rdp_settings.h"
 
-#include <freerdp/client/disp.h>
 #include <freerdp/freerdp.h>
 
+#ifdef HAVE_FREERDP_CLIENT_DISP_H
+#include <freerdp/client/disp.h>
+#endif
+
 /**
  * The minimum value for width or height, in pixels.
  */
@@ -49,10 +52,12 @@
  */
 typedef struct guac_rdp_disp {
 
+#ifdef HAVE_FREERDP_DISPLAY_UPDATE_SUPPORT
     /**
      * Display control interface.
      */
     DispClientContext* disp;
+#endif
 
     /**
      * The timestamp of the last display update request, or 0 if no request