docs: mention codec data / stream header change in porting docs
docs: mention codec data / stream header change in porting docs

justinjoy/gstreamer,mparis/gstreamer,StreamUtils/gstreamer,krichter722/gstreamer,surround-io/gstreamer,krieger-od/gstreamer,cfoch/gstreamer,lubosz/gstreamer,surround-io/gstreamer,collects/gstreamer,jpakkane/gstreamer,jpxiong/gstreamer,lovebug356/gstreamer,jpxiong/gstreamer,krieger-od/gstreamer,jpxiong/gstreamer,justinjoy/gstreamer,centricular/gstreamer,centricular/gstreamer,collects/gstreamer,mparis/gstreamer,Lachann/gstreamer,cfoch/gstreamer,shelsonjava/gstreamer,Lachann/gstreamer,ensonic/gstreamer,StreamUtils/gstreamer,jpakkane/gstreamer,lubosz/gstreamer,mparis/gstreamer,lovebug356/gstreamer,justinjoy/gstreamer,ensonic/gstreamer,lubosz/gstreamer,krichter722/gstreamer,StreamUtils/gstreamer,Lachann/gstreamer,jpakkane/gstreamer,ensonic/gstreamer,centricular/gstreamer,Lachann/gstreamer,StreamUtils/gstreamer,Lachann/gstreamer,collects/gstreamer,cfoch/gstreamer,shelsonjava/gstreamer,centricular/gstreamer,krichter722/gstreamer,ensonic/gstreamer,jpakkane/gstreamer,jpakkane/gstreamer,cablelabs/gstreamer,justinjoy/gstreamer,lubosz/gstreamer,justinjoy/gstreamer,cablelabs/gstreamer,collects/gstreamer,centricular/gstreamer,krichter722/gstreamer,cablelabs/gstreamer,mparis/gstreamer,shelsonjava/gstreamer,collects/gstreamer,shelsonjava/gstreamer,surround-io/gstreamer,cfoch/gstreamer,cfoch/gstreamer,lubosz/gstreamer,shelsonjava/gstreamer,cablelabs/gstreamer,StreamUtils/gstreamer,jpxiong/gstreamer,krieger-od/gstreamer,jpxiong/gstreamer,ensonic/gstreamer,cablelabs/gstreamer,surround-io/gstreamer,lovebug356/gstreamer,surround-io/gstreamer,krieger-od/gstreamer,lovebug356/gstreamer,lovebug356/gstreamer,mparis/gstreamer,krieger-od/gstreamer,krichter722/gstreamer