vnc: increase max display size

It's 2024.  4k display resolutions are a thing these days.
Raise width and height limits of the qemu vnc server.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1596
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-ID: <20240530111029.1726329-1-kraxel@redhat.com>

ui/vnc.h

@@ -81,8 +81,8 @@ typedef void VncSendHextileTile(VncState *vs,
 
 /* VNC_MAX_WIDTH must be a multiple of VNC_DIRTY_PIXELS_PER_BIT. */
 
-#define VNC_MAX_WIDTH ROUND_UP(2560, VNC_DIRTY_PIXELS_PER_BIT)
-#define VNC_MAX_HEIGHT 2048
+#define VNC_MAX_WIDTH ROUND_UP(5120, VNC_DIRTY_PIXELS_PER_BIT)
+#define VNC_MAX_HEIGHT 2160
 
 /* VNC_DIRTY_BITS is the number of bits in the dirty bitmap. */
 #define VNC_DIRTY_BITS (VNC_MAX_WIDTH / VNC_DIRTY_PIXELS_PER_BIT)