msdk: libva: remove unnecessary code and comments

https://bugzilla.gnome.org/show_bug.cgi?id=794276
diff --git a/sys/msdk/msdk_libva.c b/sys/msdk/msdk_libva.c
index 714e29f..af2bd2b 100644
--- a/sys/msdk/msdk_libva.c
+++ b/sys/msdk/msdk_libva.c
@@ -29,11 +29,6 @@
  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-
-/* TODO:
- *   - discover dri_path instead of having it hardcoded
- */
-
 #include <fcntl.h>
 #include <unistd.h>
 
@@ -41,9 +36,6 @@
 #include "msdk.h"
 #include "msdk_libva.h"
 
-GST_DEBUG_CATEGORY_EXTERN (gst_msdkenc_debug);
-#define GST_CAT_DEFAULT gst_msdkenc_debug
-
 struct fourcc_map
 {
   mfxU32 mfx_fourcc;