Add vz statistics for network, cpu and memory.
CHANGES from v1.
subject prefix changed from 'parallels' to 'vz'
CHANGES from v2.
1. Concering all patches - most of implementation details are moved to vz_sdk.c.
Reason is that first this makes other subsystems statistics to be
on par with block device statistics. Second, this way we eliminate
small helper functions which arise only because we can't use sdk harness.
(like prlsdkGetAdapterIndex in previous versions). Third this way
we keep all sdk details in vz_sdk.
2. cleanup patch for net device lookups is added as suggested.
3. memory stats patch stays with macros. First I wanted to
use just one big macro with conversion argument but then
i hit the VIR_DOMAIN_MEMORY_STAT_UNUSED counter which buries
this idea. Finally this variant still seems the best for me.
src/vz/vz_driver.c | 43 +++++++++-
src/vz/vz_sdk.c | 248 +++++++++++++++++++++++++++++++++++++++++----------
src/vz/vz_sdk.h | 6 ++