Log Message:
jack: Update to 1.9.21

upstream changes:
-----------------
1.9.21 Latest
=============
  o Add shell mode to jack_control (executes commands from stdin until EOF)
  o The waf autooption --example-tools introduced in 1.9.20 is now off by
    default,
  o To get the previous behavior back pass --example-tools during build.
  o This flag (and the related tools and their code) are going to be removed in
    the next release.
  o Fix alignas() on non-packed architectures
  o Fix build of jack-example-tools man pages (1.9.20 regression)
  o Fix compatibility with macOS 12
  o Fix missing symbols from jack client library (error and info callback
    pointers)
  o Fix potential memory corruption in midi_latency_test tool
  o Fix JackWeakAPI on Windows
  o Use predefined variables in pkg-config file (required for mingw)
External changes, related to macOS/Windows installer:
  o Fix application style in QJackCtl (qwindowsvistastyle.dll was missing)
  o Update QjackCtl used in macOS/Windows installers to 0.9.7

1.9.20
======
  o Add waf autooption --example-tools to allow optional build of executables,
    libraries and man pages provided by jack-example-tools (the files are built
    by default).
  o Building and installing the additional files can be disabled by using
    --example-tools=no or --no-example-tools.
  o Fix 32-bit support in ALSA driver
  o Fix incomplete ASIO support on Windows
  o Fix metadata usage with multiple users
  o Fix netsource tool missing on Windows
  o Fix semaphore usage on macOS
  o Official FreeBSD support
External changes, related to macOS/Windows installer:
  o Update Qt5 used in macOS/Windows installers to 5.12.12
  o Update QjackCtl used in macOS/Windows installers to 0.9.6