qemu: memory notifiers

This patch against qemu upstream adds notifiers hook which lets backends get notified on memory changes, and converts kvm to use it. It survived light testing.

Michael S. Tsirkin (3):
qemu: memory notifiers
kvm: move kvm_set_phys_mem around
kvm: move kvm to use memory notifiers

 cpu-common.h |   19 ++++
 exec.c       |  110 +++++++++++++++++++--
 kvm-all.c    |  310 +++++++++++++++++++++++++++++++--------------------------
 kvm.h        |    8 --
 4 files changed, 289 insertions(+), 158 deletions(-)