Update libopus to 1.5.2 and using a new place to get it from

Author: Javernaut

scripts/libopus/download.sh

@@ -2,8 +2,8 @@
 
 source ${SCRIPTS_DIR}/common-functions.sh
 
-OPUS_VERSION=1.3.1
+OPUS_VERSION=1.5.2
 
 downloadTarArchive \
   "libopus" \
-  "https://archive.mozilla.org/pub/opus/opus-${OPUS_VERSION}.tar.gz"
+  "https://downloads.xiph.org/releases/opus/opus-${OPUS_VERSION}.tar.gz"