Corrected a mispelling of "unimplemented".

Corrected a mispelling of "unimplemented".

arch/sparc/stacktrace.hh:
    - Change the StackTrace code so that the class can more easily be
    cleaned out and reused to avoid extra allocations.
    - Allow trace() to accept a static instruction pointer so it can
    determine if the instruction is worth tracing.  This is moved from
    the CPU.
    - provide constants for special meaning PCs (user, console, unknown),
    instead of magic numbers
arch/sparc/stacktrace.hh:
    Added some typedefs for Addr and MachInst, and untemplatized StaticInstPtr
arch/sparc/stacktrace.hh:
    Made Addr a global type
arch/sparc/stacktrace.hh:
    bk cp ../alpha/stacktrace.hh stacktrace.hh

--HG--
extra : convert_revision : 8fd15e5ec8d676d081380b21886234561c5f3678