Build OpenBSD Kernel
       I'm running  OpenBSD-current for a while  in order to support  my port.
       It's currently only one port, but that's a start, right?
       Anyway... every once in a while I stumble over a patch on the OpenBSD
       Mailinglist I want to try and this requires me to apply the patch and
       build the Kernel with it. But how?
       Well, the documentation is where you would expect it:
       Download the kernel source
           $ cd /usr
           $ cvs -qd checkout -P src
       Update the kernel source
           $ cd /usr/src
           $ cvs -q up -Pd
       Configure Kernel
           $ cd /usr/src/sys/arch/amd64/conf
           $ cp GENERIC.MP MYKERNEL
           $ config MYKERNEL
       Build and install kernel (amd64)
           $ cd /sys/arch/amd64/compile/MYKERNEL
           $ make clean
           $ make
           $ make install # the old kernel is /obsd now
       That's it. Reboot.
       This is ONLY the Kernel. If you need to build the whole system, please
       consult the OpenBSD documentation.
       # Changelog:
       # * 2019-10-24: Created