uwac: Fix connection between mouse-less devices

In case the seat has no default_cursor, which happens on client device with
no mouse attached (e.g. tablets), freerdp would fail to connect because it
won't be able to set cursor image. Check for this condition and skip setting
the cursor image.

Signed-off-by: Marek Vasut <marex@denx.de>

uwac/libuwac/uwac-input.c

@@ -1191,5 +1191,7 @@ UwacReturnCode UwacSeatSetMouseCursor(UwacSeat* seat, const void* data, size_t l
 	{
 		seat->pointer_type = 1;
 	}
+	if (seat && !seat->default_cursor)
+		return UWAC_SUCCESS;
 	return set_cursor_image(seat, seat->display->serial);
 }