filter-chain: parse config options

Remove LADSPA dependencies, only use it in ladspa_plugin.c
Parse convolver config, like filename

src/daemon/filter-chain/sink-convolver.conf

@@ -36,6 +36,10 @@ context.modules = [
                         type = builtin
                         name = convolver
                         label = convolver
+			config = {
+			   filename = "src/modules/module-filter-chain/street2-L.wav"
+			   blocksize = 512
+			}
                     }
                 ]
             }