libc: Add initial sysvipc Symbol map (untested)
libmd: Fix some manual page prototypes.
x86_64: Detect CPU specific C-state through CPUID(5)

The information is exposed through machdep.mwait sysctl nodes

This could be used to:
- Validate cpu_mwait_halt
- Validate cpu_mwait_spin
- Prepare to turn on C1/C2/C3 native support in ACPI _OSC evalution