Attached is a simple patch to make i2c_bus_save() put a 32-bit quantity in the
save file, which matches what i2c_bus_load() expects to pull out of the save
file later.  Without this fix in place, KVM live migration fails since the
sender is only sending 1 byte while the receiver is waiting to receive 4 bytes.

Avi, I don't know when you plan to next rebase KVM to upstream QEMU, but it's
probably a good idea to carry this patch so that live migration works at all.

Signed-off-by: Chris Lalancette <clalance@redhat.com>