tests: monitor: json: Fix error message when returning json in json

The qemu JSON monitor test allows to test also expected command
arguments. As the error from the monitor simulator is returned as a
simulated qemu error (in JSON) all other JSON contained in the error
message needs to be escaped. This will happen if the monitor command
under test receives a JSON array as an argument.

This will improve the error message from:
libvirt:  error : internal error: cannot parse json { "error":  { "desc":
"Invalid value of argument 'keys' of command 'send-key': expected 'ble'
got '[{"type":"number","data":43},{"type":"number","data":26},
{"type":"number","data":46},{"type":"number","data":32}]'",
"class": "UnexpectedCommand" } }: lexical error: invalid string in json text.

To:
libvirt: QEMU Driver error : internal error: unable to execute QEMU
command 'send-key': Invalid value of argument 'keys' of command
'send-key': expected 'ble' got '[{"type":"number","data":43},
{"type":"number","data":26},{"type":"number","data":46},
{"type":"number","data":32}]'

This improvement will not have any effect on tests executing as
expected, but it will help test development.
virnuma: Introduce virNumaGetDistances

The API gets a NUMA node and find distances to other nodes.  The
distances are returned in an array. If an item X within the array
equals to value of zero, then there's no such node as X.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
virCaps: Expose distance between host NUMA nodes

If user or management application wants to create a guest,
it may be useful to know the cost of internode latencies
before the guest resources are pinned. For example:

<capabilities>

  <host>
    ...
    <topology>
      <cells num='2'>
        <cell id='0'>
          <memory unit='KiB'>4004132</memory>
          <distances>
            <sibling id='0' value='10'/>
            <sibling id='1' value='20'/>
          </distances>
          <cpus num='2'>
            <cpu id='0' socket_id='0' core_id='0' siblings='0'/>
            <cpu id='2' socket_id='0' core_id='2' siblings='2'/>
          </cpus>
        </cell>
        <cell id='1'>
          <memory unit='KiB'>4030064</memory>
          <distances>
            <sibling id='0' value='20'/>
            <sibling id='1' value='10'/>
          </distances>
          <cpus num='2'>
            <cpu id='1' socket_id='0' core_id='0' siblings='1'/>
            <cpu id='3' socket_id='0' core_id='2' siblings='3'/>
          </cpus>
        </cell>
      </cells>
    </topology>
    ...
  </host>
  ...
</capabilities>

We can see the distance from node1 to node0 is 20 and within nodes 10.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
virnuma: Implement virNumaGetDistances stub for non-NUMA

In case the libvirt is built without numactl support, we're
missing the virNumaGetDistances() stub so the linking fails:

  CCLD     libvirt_lxc
libvirt_lxc-nodeinfo.o: In function `virNodeCapsGetSiblingInfo':
/home/zippy/tmp/libvirt.git/src/nodeinfo.c:1763: undefined reference to `virNumaGetDistances'
collect2: error: ld returned 1 exit status
make[3]: *** [libvirt_lxc] Error 1

The issue was introduced in 77c830d8c4.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
cfg.mk: Introduce rule for setlocale()

In the past we had some issues where setlocale() was called without
corresponding include of locale.h. While on some systems this may
work, on others the compilation failed. We should have a syntax-check
rule for that to prevent this from happening again.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
translations: Don't leave default template fields in .po files

New gettext-0.19 doesn't like it and we can't build without it.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>