Adapt the top utility to not use kmem_read to retrieve variables now available via sysctl().  As a result, top should now be able to run without setgid kmem.
Adapt the top utility to not use kmem_read to retrieve variables now
available via sysctl().  As a result, top should now be able to run without
setgid kmem.

Submitted by:	Thomas Moestl <tmoestl@gmx.net>
Reviewed by:	freebsd-audit

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase