[libvirt] [PATCH v2] Use virGetLastErrorMessage() rather than open code it

[Cole Robinson]

When sending a v2, please give a description of what changed compared to the
previous patch version, after the --- break so it doesn't show up in the
commit message. For example:

On 04/04/2016 06:49 AM, Hui Yiqun wrote:
> getting err using virGetLastError() and then retrieving
> message from err asks developers to test the value
> of err and err->message and default to self-defined
> unkown error message.
> 
> It's better to avoid it and use uniform
> virGetLastErrorMessage
> ---

v2:
  * Fixed the FOO
  * Replaces the BAZ
  * etc

>  daemon/libvirtd.c                   |  8 +---
>  examples/object-events/event-test.c |  9 ++---
>  src/bhyve/bhyve_driver.c            |  3 +-
>  src/libvirt.c                       |  3 +-
>  src/libxl/libxl_domain.c            |  3 +-
>  src/libxl/libxl_driver.c            |  3 +-
>  src/locking/lock_daemon.c           |  8 +---
>  src/logging/log_daemon.c            |  8 +---
>  src/lxc/lxc_container.c             |  8 +---
>  src/lxc/lxc_controller.c            |  8 +---
>  src/lxc/lxc_domain.c                |  3 +-
>  src/lxc/lxc_process.c               |  6 +--
>  src/network/bridge_driver.c         |  3 +-
>  src/node_device/node_device_hal.c   |  3 +-
>  src/rpc/virnettlscontext.c          |  3 +-
>  src/secret/secret_driver.c          |  6 +--
>  src/storage/storage_driver.c        | 16 ++------
>  src/uml/uml_driver.c                |  3 +-
>  src/util/iohelper.c                 | 10 +----
>  src/util/virhook.c                  |  3 +-
>  src/util/virhostdev.c               | 20 ++++-----
>  tests/commandtest.c                 | 81 +++++++++++++------------------------
>  tests/libvirtdconftest.c            |  3 +-
>  tests/openvzutilstest.c             |  7 +---
>  tests/securityselinuxlabeltest.c    |  9 ++---
>  tests/securityselinuxtest.c         |  6 +--
>  tests/virnettlscontexttest.c        |  3 +-
>  27 files changed, 77 insertions(+), 169 deletions(-)

There's still at least one build error 'error: unused
variable 'err'' in here. Please review the code carefully, or only send the
patch targetting the drivers that you can actually build test.

Thanks,
Cole