* "configure --disable-ssp" to avoid the dependency on libssp.
* Enable x86_64.
* Use 18.1.1 for the lib versions, instead of $portVersion.
* Replace cmd:libtool by cmd:libtoolize$secondaryArchSuffix.
* Change prepareInstalledDevelLibs to prepareInstalledDevelLib,
since we have only one lib here.