SDL: Fixed building with the steamrt/scout SDK (0811b)

From 0811b4dc515d8ab7f792d72e48729a27a373b72a Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Fri, 19 Jan 2024 23:02:48 -0800
Subject: [PATCH] Fixed building with the steamrt/scout SDK

(cherry picked from commit 4b82bed2599395cb3a37704f41ec7d1a37466cb8)
(cherry picked from commit ecde0ca6b661f21ef4d482afadc20e8156f8e321)
---
 src/video/kmsdrm/SDL_kmsdrmvideo.h | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/src/video/kmsdrm/SDL_kmsdrmvideo.h b/src/video/kmsdrm/SDL_kmsdrmvideo.h
index 1f7796496e0e4..9c8ebe85e099d 100644
--- a/src/video/kmsdrm/SDL_kmsdrmvideo.h
+++ b/src/video/kmsdrm/SDL_kmsdrmvideo.h
@@ -33,9 +33,26 @@
 #include <gbm.h>
 #include <EGL/egl.h>
 
+#ifndef DRM_MODE_PAGE_FLIP_ASYNC
+#define DRM_MODE_PAGE_FLIP_ASYNC    2
+#endif
+
+#ifndef DRM_MODE_OBJECT_CONNECTOR
+#define DRM_MODE_OBJECT_CONNECTOR   0xc0c0c0c0
+#endif
+
+#ifndef DRM_MODE_OBJECT_CRTC
+#define DRM_MODE_OBJECT_CRTC        0xcccccccc
+#endif
+
+#ifndef DRM_CAP_ASYNC_PAGE_FLIP
+#define DRM_CAP_ASYNC_PAGE_FLIP 7
+#endif
+
 #ifndef DRM_CAP_CURSOR_WIDTH
 #define DRM_CAP_CURSOR_WIDTH    8
 #endif
+
 #ifndef DRM_CAP_CURSOR_HEIGHT
 #define DRM_CAP_CURSOR_HEIGHT   9
 #endif