Include hwcontex.h and add drm header option

Author: sethdusek

sys/build.rs

@@ -993,7 +993,8 @@ fn main() {
         .header(search_include(&include_paths, "libavutil/timecode.h"))
         .header(search_include(&include_paths, "libavutil/twofish.h"))
         .header(search_include(&include_paths, "libavutil/avutil.h"))
-        .header(search_include(&include_paths, "libavutil/xtea.h"));
+        .header(search_include(&include_paths, "libavutil/xtea.h"))
+	.header(search_include(&include_paths, "libavutil/hwcontext.h"));
 
     if env::var("CARGO_FEATURE_POSTPROC").is_ok() {
         builder = builder.header(search_include(&include_paths, "libpostproc/postprocess.h"));
@@ -1007,6 +1008,10 @@ fn main() {
         builder = builder.header(search_include(&include_paths, "libswscale/swscale.h"));
     }
 
+    if env::var("CARGO_FEATURE_LIB_DRM").is_ok() {
+        builder = builder.header(search_include(&include_paths, "libavutil/hwcontext_drm.h"))
+    }
+
     // Finish the builder and generate the bindings.
     let bindings = builder.generate()
     // Unwrap the Result and panic on failure.