target-arm/machine.c: Convert to VMStateDescription.

This patch modifies the ARM CPU state load/save routines to use
a VMStateDescription instead of explicit load/save routines.

+ Get rid of obsolete target-arm/qom-cpu.h (instead cpu-qom.h is
  being used).

Change-Id: I7e2e00fad18fd670c3b4ca50b1dcd4f9b9dcbe0b
5 files changed