inputselector: Send upstream events to all sinkpads, not only the selected one
inputselector: Send upstream events to all sinkpads, not only the selected one

This makes sure that SEEK events are sent to all upstream elements, which is
required if different streams are completely distinct pipeline parts. Also this
allows QoS to be done on deselected streams, flushes to be handled correctly,
etc.

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