Log Message:
libffi: update to 3.4.7.

3.4.7 Feb-8-2024
      Add static trampoline support for Linux on s390x.
      Fix BTI support for ARM64.
      Support pointer authentication for ARM64.
      Fix ASAN compatibility.
      Fix x86-64 calls with 6 GP registers and some SSE registers.
      Miscellaneous fixes for ARC and Darwin ARM64.
      Fix OpenRISC or1k and Solaris 10 builds.
      Remove nios2 port.