extra/libdrm: add patch

extra/libdrm/0001-xf86drm-Fix-ioctl-struct-clearing-in-drmAgpEnable.patch

@@ -0,0 +1,28 @@
+From 7d8f5e019505f5bda67ad8d2b25077eade90fbe8 Mon Sep 17 00:00:00 2001
+From: Connor Behan <connor.behan@gmail.com>
+Date: Tue, 24 Mar 2015 13:47:26 -0400
+Subject: [PATCH] xf86drm: Fix ioctl struct clearing in drmAgpEnable
+
+This one is a bit harder to notice.
+
+Signed-off-by: Connor Behan <connor.behan@gmail.com>
+---
+ xf86drm.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/xf86drm.c b/xf86drm.c
+index e73cddd..ffc53b8 100644
+--- a/xf86drm.c
++++ b/xf86drm.c
+@@ -1719,7 +1719,7 @@ int drmAgpEnable(int fd, unsigned long mode)
+ {
+     drm_agp_mode_t m;
+ 
+-    memclear(mode);
++    memclear(m);
+     m.mode = mode;
+     if (drmIoctl(fd, DRM_IOCTL_AGP_ENABLE, &m))
+ 	return -errno;
+-- 
+2.3.3
+