Even though JFrog continued Bintray normal operation until 31 Mar 2021, I'm
disabling Github Actions uploads now. Termux Bintray repository continues to
be available in read-only mode until the final shutdown by JFrog.
* Fix ghostscript for aarch64.
* ghostscript: fix arm header
* ghostscript: clean build script
* ghostscript: disable i686 and x86_64 for now and enable package!
* Add required build dependencies for ghostscript to setup scripts
* ghostscript: add libexpat as dependency
* ghostscript: add (untested) generated headers for x86_64 and i686