echo-cancel: Use common code

This module cannot be fully consolidated, but still there are significant savings.
With some re-ordering, probably even more of the code could be converted.

src/modules/meson.build

@@ -262,7 +262,7 @@ module_echo_cancel_sources = [
 module_echo_cancel_orc_sources = []
 module_echo_cancel_flags = []
 module_echo_cancel_deps = [libatomic_ops_dep]
-module_echo_cancel_libs = []
+module_echo_cancel_libs = [libvirtual_sink]
 
 if get_option('adrian-aec')
   module_echo_cancel_sources += [