Get TSC frequency from CPUID 0x15 and/or x16 for newer Intel processors.

- If the max CPUID leaf is >= 0x15, take TSC value from CPUID. Some processors
can take TSC/core crystal clock ratio but core crystal clock frequency
can't be taken. Intel SDM give us the values for some processors.
- It also required to change lapic_per_second to make LAPIC timer correctly.
- Add new file x86/x86/identcpu_subr.c to share common subroutines between
kernel and userland. Some code in x86/x86/identcpu.c and cpuctl/arch/i386.c
will be moved to this file in future.
- Add comment to clarify.

branches: 1.6.4; 1.6.6;
implement cpuctl identify for sparc and sparc64.

sparc:
- move enum vactype and struct cacheinfo into cpu.h
- move the cache flags from cpuinfo.flags into CACHEINFO.c_flags
(this allows the new cache_printf_backend() to see them.)
remove unused CPUFLG_CACHEIOMMUTABLES and CPUFLG_CACHEDVMA.
- align xmpsg to 64 bytes
- move cache_print() into cache_print.h so it can be shared with
cpuctl. it only depends upon a working printf().
- if found, store the CPU node's "name" into cpu_longname. this
changes the default output to show the local CPU not the
generic CPU family. eg:
cpu0 at mainbus0: mid 8: Ross,RT625 @ 90 MHz, on-chip FPU
vs the generic "RT620/625" previously shown.
- for each CPU export these things:
- name
- fpuname
- mid
- cloc
- freq
- psr impl and version
- mmu impl, version, and number of contexts
- cacheinfo structure (which changed for the first time ever
with this commit.)

sparc64:
- add a minimal "cacheinfo" structure to export the i/d/e-cache
size and linesize.
- store %ver, cpu node "name" and cacheinfo in cpu_info.
- set cpu_info ver, name and cacheinfo in cpu_attach(), and
export them via sysctl, as well as CPU ID and clock freq

cpuctl:
- add identifycpu_bind() that returns false on !x86 as their
identify routines do not need to run on a particular CPU to
obtain its information, and use it to avoid trying to set
affinity when not needed.
- add sparc and sparc64 cpu identify support using the newly
exported values.

branches: 1.5.18;
Add verbose flag.
On x86 cpu, cpuctl -v identify dumps the return values of the cpuid
functions. The max levels are taken from CPUID 0 and CPUID 8000_0000.
It's useful for the future CPU.

branches: 1.4.2;
Extend the CPU microcode update framework to support Intel x86 CPUs.
Contrary to the AMD implementation, it doesn't use xcalls to distribute
the update to all CPUs but relies on cpuctl(8) to bind itself to the
right CPU -- to keep it simple and avoid possible problems with
hyperthreading.
Also, it doesn't parse the vendor supplied file to pick the right
part for the present CPU model but relies on userland to prepare
files with specific filenames. I'll commit a pkg for this in a minute
(pkgsrc/sysutils/intel-microcode).
The ioctl interface changed; compatibility is provided (should be
limited to COMPAT_NETBSD6 as soon as this is available).

Add __printflike attribution to use vprintf and friends with an argument
as format string.

branches: 1.2.8; 1.2.10;
Remove 3rd buggy copy of this function and use snprintb(3) instead.
No need to allocate MAXPATHLEN buffers anymore.

branches: 1.1.4; 1.1.8;
PR port-amd64/37461 x86 cpu dmesg output is noisy

Port identifycpu() to userspace. The kernel lies and reports on cpuN while
actually using the values from cpu0, but this attempts to bind itself to the
requested CPU if running as root. That doesn't work properly yet due to
kern/38588, but will do once that's fixed.