tor/changes/bug40465

  o Major bugfixes (sandbox):
    - Fix sandbox to work on architectures that use Linux's generic syscall
      interface, extending support for AArch64 (ARM64) and adding support for
      RISC-V, allowing test_include.sh and the sandbox unit tests to pass on
      these systems even when building with fragile hardening enabled. Fixes
      bugs 40465 and 40599; bugfix on 0.2.5.1-alpha.