multimedia/ffmpeg: speed up DRM (kmsgrab), OPENCL, VAAPI, VULKAN

https://github.com/ffmpeg/ffmpeg/commit/993d8d94296e

multimedia/ffmpeg/Makefile

@@ -1,6 +1,6 @@
 PORTNAME=	ffmpeg
 PORTVERSION=	4.4.3
-PORTREVISION=	5
+PORTREVISION=	6
 PORTEPOCH=	1
 CATEGORIES=	multimedia audio net
 MASTER_SITES=	https://ffmpeg.org/releases/

multimedia/ffmpeg/files/patch-libavutil_hwcontext__drm.c

@@ -0,0 +1,24 @@
+drm-kmod doesn't expose uAPI yet, so bundle like Mesa
+
+--- libavutil/hwcontext_drm.c.orig	2022-07-22 17:58:39 UTC
++++ libavutil/hwcontext_drm.c
+@@ -28,6 +28,19 @@
+ #if HAVE_LINUX_DMA_BUF_H
+ #include <linux/dma-buf.h>
+ #include <sys/ioctl.h>
++#else // BSDs
++#undef HAVE_LINUX_DMA_BUF_H
++#define HAVE_LINUX_DMA_BUF_H 1
++#include <sys/ioctl.h>
++struct dma_buf_sync {
++	uint64_t flags;
++};
++#define DMA_BUF_BASE		'b'
++#define DMA_BUF_IOCTL_SYNC	_IOW(DMA_BUF_BASE, 0, struct dma_buf_sync)
++#define DMA_BUF_SYNC_READ      (1 << 0)
++#define DMA_BUF_SYNC_WRITE     (2 << 0)
++#define DMA_BUF_SYNC_START     (0 << 2)
++#define DMA_BUF_SYNC_END       (1 << 2)
+ #endif
+ 
+ #include <drm.h>