Relax the object locking assertion in vm_page_lookup().  Now that a radix
tree is used to maintain the object's collection of resident pages,
vm_page_lookup() no longer needs an exclusive lock.

Reviewed by:    attilio
Sponsored by:   EMC / Isilon Storage Division
- Update the release notes to DocBook 4.5 XML to build with the
  updated documentation tree
Relax the object locking assertion in pmap_enter_locked().

Reviewed by:	attilio
Sponsored by:	EMC / Isilon Storage Division
Relax the object locking in vm_fault_prefault().  A read lock suffices.

Reviewed by:	attilio
Sponsored by:	EMC / Isilon Storage Division
o  Retrive the part number (CP2103 etc) from the hardware on attach.
o  The CP2101 and CP2102 do not support GPIO pin use at all, enforce this.
o  Support reading the GPIO status on the second port of the CP2105.  More
   work is needed before the CP2105 GPIO pins can be used as outputs.

Hardware donated by:	Silicon Labs
MFC after:		3 weeks