Create a new CpuEvent class that has a pointer to an execution context in the object...

Create a new CpuEvent class that has a pointer to an execution context in the object and places itself on a global list so
so the events can be migrated on cpu switches.
Create a new wrapper classe called CpuEventWrapper that works like the old wrapper class but calls the function with the xc
parameter
Use new CpuEventWrapper class from tick compare events on sparc

src/arch/sparc/regfile.hh:
    Use new CpuEventWrapper class from tick compare events
src/arch/sparc/ua2005.cc:
    Move definition to to a fullsystem only file, since it is.
src/cpu/base.cc:
    On switch from one cpu to another CpuEvent::replaceExecContext() needs to be called on all (oldxc,newxc) pairs.

--HG--
extra : convert_revision : eecf4540427cc0ddf75e19a3371cf32b56cba0f5