porting: update porting doc
porting: update porting doc

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