Add GitHub Actions workflow to build ZLMediaKit for linux/arm64
(aarch64) using the native ubuntu-24.04-arm runner.
- Build container: debian:11 (glibc 2.31) for broad compatibility
- Compile steps extracted into package/build_linux_arm64.sh for
debugging
- OpenSSL: no-asm/no-dso/-fPIC to fix aarch64 PIC relocation issues
- Artifacts: Linux_ARM64_<branch>_<date>
Successfully tested on my fork; artifact includes MediaServer and
related binaries.
Co-authored-by: yangheng <492238647@qq.com>