Several fixes for the PCID implementation:

- When clearing a bit for a cpuid in pmap->pm_save, ensure that the
  cpuid is not set in pm_active.  The pm_save indicates which CPUs may
  have cached translations for given PCID, which implies that a CPU
  executing with the given pmap active have the translations
  cached. [1]

- In smp_masked_invltlb(), pass pmap to smp_targeted_tlb_shootdown(). [1]

- In invlrng_handler(), check for the special values of pcid (0 and
  -1) and do corresponding global or total invalidations before
  checking for performing PCID-specific range invalidation with
  INVPCID_ADDR. [2]

- In invltlb_pcid_handler(), do not read %cr3 unless needed. [2]

- Do minor style tweaks. [2]

Submitted by:	Henrik Gulbrandsen <henrik@gulbra.net> [1]
Other parts sponsored by:	The FreeBSD Foundation [2]
Tested by:	Henrik Gulbrandsen, pho
MFC after:	1 week
Add `-S' to display syscall numbers in the output as well.

This is useful for debugging compat modules.

Sponsored by:	EMC / Isilon Storage Division
Obtained from:	Isilon OneFS (based on work by Jeff Hughes)
MFC after:	2 weeks