decproxy: add audio/x-raw on static src pad template
decproxy: add audio/x-raw on static src pad template

decproxy static src pad template was changed from audio/x-raw to audio/x-media
for supporting audio/x-raw contents.
However it can cause pipeline construction problem at custom pipeline,
so decproxy is having both audio/x-raw and audio/x-media static caps on
its src template.

:issues addressed:
[BHV-14262] send media-info in audio/x-raw case

Change-Id: Iee01f5148cc9d4083843ea8b42724e812e92f729
Reviewed-on: https://gpro.lgsvl.com/63561
Reviewed-by: Jeongseok Kim <0c03ab7a1b32f29697716389c3f9549845834271@lge.com>
Tested-by: Jeongseok Kim <0c03ab7a1b32f29697716389c3f9549845834271@lge.com>

justinjoy/gst-plugins-cool,justinjoy/gst-plugins-cool