Fix sed script for version-independent .pc file

The mozjs.pc file is no longer named in old-configure.in (doesn't exist)
but in js/moz.configure.

Author: ptomato

tools/generic_lib.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
 # Make SpiderMonkey and this repo generic instead of version specific.
 # script shoud be run in mozjs dir with $1 for meson.build location
-sed -i 's/mozjs-$MOZILLA_SYMBOLVERSION/mozjs/g' old-configure.in
+sed -i 's/mozjs-\{symbolversion\}/mozjs/g' js/moz.configure
 sed -i --regexp-extended "s/dependency\(.mozjs.*$/dependency('mozjs')/gm" "$1"