package/ffmpeg: add optional support for libdrm

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/ffmpeg/ffmpeg.mk

@@ -231,6 +231,13 @@ ifeq ($(BR2_PACKAGE_FFMPEG_GPL)$(BR2_PACKAGE_LIBEBUR128),yy)
 FFMPEG_DEPENDENCIES += libebur128
 endif
 
+ifeq ($(BR2_PACKAGE_LIBDRM),y)
+FFMPEG_CONF_OPTS += --enable-libdrm
+FFMPEG_DEPENDENCIES += libdrm
+else
+FFMPEG_CONF_OPTS += --disable-libdrm
+endif
+
 ifeq ($(BR2_PACKAGE_LIBOPENH264),y)
 FFMPEG_CONF_OPTS += --enable-libopenh264
 FFMPEG_DEPENDENCIES += libopenh264