pid1: add new kernel cmdline arg systemd.cpu_affinity=
    
    Let's allow configuration of the CPU affinity via the kernel cmdline,
    overriding CPUAffinity= in /etc/systemd/system.conf
    
    Prompted by:
    
    https://lists.freedesktop.org/archives/systemd-devel/2019-November/043754.html
    
    (cherry picked from commit 68d58f38693e586b5ce5785274f8e42a79625196)
    
    Resolves: #1812894
    
    patch_name: 0370-pid1-add-new-kernel-cmdline-arg-systemd.cpu_affinity.patch
    present_in_specfile: true
    location_in_specfile: 370
    squash_commits: true