[PARISC] pdc_stable version 0.22

pdc_stable v0.22, changes since v0.10:

  o renamed root subsystem from 'pdc' to 'stable'
  o split 'info' into several files, one per PDC field
  o implemented 'autoboot' and 'autosearch' write calls to toggle
    these flags
  o grant read permission to all users on "safe" files
  o more code cleanup (removed duplicate code)
  o avoid bad stable storage clobbering by write locking critical sections
  o print consistent data as well
  o SMP cleanups

Signed-off-by: Thibaut VARENE <varenet@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>