Fix breakage after r267981.

Pointy hat to:	dim
MFC after:	3 days
X-MFC-With:	r267981
Don't accidently skip every second line when calculating the
idle time.

MFC after:	2 weeks
Compile fixes:

Remove duplicate "debug_ktr.mask" sysctl definition.
Remove now unused variable from "kern_ktr.c".
This fixes build of "ktr" which was broken by r267961.

Let the default value for "vm_kmem_size_scale" be zero. It is setup
after that the sysctl has been initialized from "getenv()" in the
"kmeminit()" function to equal the "VM_KMEM_SIZE_MAX" value, if
zero. On Sparc64 the "VM_KMEM_SIZE_MAX" macro is not a constant. This
fixes build of Sparc64 which was broken by r267961.

Add a special macro to dynamically create SYSCTL root nodes, because
root nodes have a special parent. This fixes build of existing OFED
module and CANBUS module for pc98 which was broken by r267961.

Add missing "sysctl.h" includes to get the needed sysctl header file
declarations. This is needed after r267961.

MFC after:	2 weeks
Move the -I of common/util to the proper place to fix the powerpc build.

MFC after:	2 weeks
Revert	r267869:

MFV	r260708
4427 pid provider rejects probes with valid UTF-8 names

Use of u8_textprep.c broke the build on powerpc.

Reported by:	bz, rpaulo and tinderbox.
Pointyhat:	me
Fix build with gcc.
Merge remote-tracking branch 'upstream/master'
Remove unneeded include.
Really fix build with autofs.