cmake: Update to 3.20.3

cmake: Update to 3.20.3

- Update from 3.20.2 to 3.20.3
- Update of rootfile not required
- Changelog
   Changes made since CMake 3.20.2:
   Brad King (7):
    Help: Use relative path for IDE Integration guide link to preset schema
    BinUtils: Use more-private temporary variable names
    ObjectiveC: Respect OSX_ARCHITECTURES for OBJC
    FindBoost: Add support for Boost 1.76
    Ninja: Restore support for Fortran in a symlinked build tree
    Utilities/Sphinx: Update man page config for Sphinx 4
    CMake 3.20.3
   Craig Scott (2):
    ExternalProject: Ensure git fetch if updating to hash we don’t have yet
    ExternalProject: Only add git config setting with git 1.7.7 or later
   Kyle Edwards (2):
    Ninja Multi-Config: Split long command lines by config
    CMP0082: Check EXCLUDE_FROM_ALL property at generate time
   Raul Tambre (3):
    GNU: C++17 default version
    GNU: Final C++20 flags
    GNU: C++23 support
   Robert Maynard (6):
    CUDA: improve regex for CUDA Toolkit root from nvcc verbose output
    cmCommandLineArgument: Correctly record parsing failures
    cmake: --build and --install error out when encountering bad flags
    cmCommandLineArgument: Provide more information syntax error messages
    NVHPC: Support explicit language flags
    NVHPC: Support Ninja dependency scanning

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>