target-ppc: Extend FPU state for newer POWER CPUs

target-ppc: Extend FPU state for newer POWER CPUs

This patch adds some extra FPU state to CPUPPCState.  Specifically,
fpscr is extended to a target_ulong bits, since some recent (64 bit)
CPUs now have more status bits than fit inside 32 bits.  Also, we add
the 32 VSR registers present on CPUs with VSX (these extend the
standard FP regs, which together with the Altivec/VMX registers form a
64 x 128bit register file for VSX).

We don't actually support the instructions using these extra registers
in TCG yet, but we still need a place to store the state so we can
sync it with KVM and savevm/loadvm it.  This patch updates the savevm
code to not fail on the extended state, but also does not actually
save it - that's a project for another patch.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>