docs: merge QoS message fields
docs: merge QoS message fields

There was already a section about QoS messages that is now merged with the new
information.

jpakkane/gstreamer,lubosz/gstreamer,mrchapp/gstreamer,ahmedammar/platform_external_gst_gstreamer,StreamUtils/gstreamer,StreamUtils/gstreamer,jpakkane/gstreamer,mparis/gstreamer,justinjoy/gstreamer,collects/gstreamer,shelsonjava/gstreamer,drothlis/gstreamer,Lachann/gstreamer,cfoch/gstreamer,magcius/gstreamer,drothlis/gstreamer,centricular/gstreamer,magcius/gstreamer,jpxiong/gstreamer,lovebug356/gstreamer,cfoch/gstreamer,magcius/gstreamer,surround-io/gstreamer,ylatuya/gstreamer,jpxiong/gstreamer,Distrotech/gstreamer,lubosz/gstreamer,lubosz/gstreamer,ensonic/gstreamer,ahmedammar/platform_external_gst_gstreamer,krieger-od/gstreamer,jpxiong/gstreamer,Lachann/gstreamer,surround-io/gstreamer,Distrotech/gstreamer,cablelabs/gstreamer,collects/gstreamer,mparis/gstreamer,shelsonjava/gstreamer,krichter722/gstreamer,krieger-od/gstreamer,justinjoy/gstreamer,shelsonjava/gstreamer,collects/gstreamer,jpakkane/gstreamer,cfoch/gstreamer,ensonic/gstreamer,mrchapp/gstreamer,lovebug356/gstreamer,shelsonjava/gstreamer,collects/gstreamer,Distrotech/gstreamer,magcius/gstreamer,ylatuya/gstreamer,drothlis/gstreamer,lovebug356/gstreamer,surround-io/gstreamer,ylatuya/gstreamer,krieger-od/gstreamer,StreamUtils/gstreamer,mparis/gstreamer,krieger-od/gstreamer,lubosz/gstreamer,drothlis/gstreamer,cablelabs/gstreamer,drothlis/gstreamer,StreamUtils/gstreamer,magcius/gstreamer,ahmedammar/platform_external_gst_gstreamer,Distrotech/gstreamer,lovebug356/gstreamer,cfoch/gstreamer,ylatuya/gstreamer,Lachann/gstreamer,centricular/gstreamer,jpakkane/gstreamer,centricular/gstreamer,mrchapp/gstreamer,ensonic/gstreamer,centricular/gstreamer,mrchapp/gstreamer,collects/gstreamer,krichter722/gstreamer,justinjoy/gstreamer,krichter722/gstreamer,Lachann/gstreamer,cablelabs/gstreamer,ensonic/gstreamer,cfoch/gstreamer,krichter722/gstreamer,jpakkane/gstreamer,mparis/gstreamer,jpxiong/gstreamer,surround-io/gstreamer,cablelabs/gstreamer,ahmedammar/platform_external_gst_gstreamer,lovebug356/gstreamer,justinjoy/gstreamer,Lachann/gstreamer,jpxiong/gstreamer,shelsonjava/gstreamer,cablelabs/gstreamer,ensonic/gstreamer,centricular/gstreamer,ahmedammar/platform_external_gst_gstreamer,mrchapp/gstreamer,krichter722/gstreamer,lubosz/gstreamer,surround-io/gstreamer,justinjoy/gstreamer,mparis/gstreamer,StreamUtils/gstreamer,ylatuya/gstreamer,Distrotech/gstreamer,krieger-od/gstreamer