qemu-replies-tool: Add mode to dump all QMP schema query strings

qemu-replies-tool: Add mode to dump all QMP schema query strings

Make the tool useful also for non-testing purposes by adding 'dump'
mode, which will process the data and output information about the qemu
version.

The first 'dump' mode produces all possible valid query strings per
virQEMUQAPISchemaPathGet/virQEMUCapsQMPSchemaQueries. This is useful for
users to look up a query string via 'grep' rather than trying to come up
with it manually.

Additionally the data as represented by qemu changes naming very often
and that makes it un-reviewable to find changes between two qemu builds.
By using the dump mode, which produces results in stable order we can
use it to 'diff' two .replies file without churn.

Sample output '[...]' denotes an arbitrary trim:

$ ./scripts/qemu-replies-tool.py tests/qemucapabilitiesdata/caps_9.0.0_x86_64.replies --dump-qmp-query-strings
[...]
(qmp) blockdev-add
(qmp) blockdev-add/arg-type/auto-read-only
(qmp) blockdev-add/arg-type/auto-read-only/!bool
(qmp) blockdev-add/arg-type/cache
(qmp) blockdev-add/arg-type/cache/direct
(qmp) blockdev-add/arg-type/cache/direct/!bool
(qmp) blockdev-add/arg-type/cache/no-flush
(qmp) blockdev-add/arg-type/cache/no-flush/!bool
(qmp) blockdev-add/arg-type/detect-zeroes
(qmp) blockdev-add/arg-type/detect-zeroes/^off
(qmp) blockdev-add/arg-type/detect-zeroes/^on
(qmp) blockdev-add/arg-type/detect-zeroes/^unmap
[...]
(qmp) blockdev-add/arg-type/driver
(qmp) blockdev-add/arg-type/driver/^blkdebug
(qmp) blockdev-add/arg-type/driver/^blklogwrites
(qmp) blockdev-add/arg-type/driver/^blkreplay
(qmp) blockdev-add/arg-type/driver/^blkverify
(qmp) blockdev-add/arg-type/driver/^bochs
(qmp) blockdev-add/arg-type/driver/^cloop
[...]
(qmp) blockdev-add/arg-type/+blkdebug
(qmp) blockdev-add/arg-type/+blkdebug/align
(qmp) blockdev-add/arg-type/+blkdebug/align/!int
(qmp) blockdev-add/arg-type/+blkdebug/config
(qmp) blockdev-add/arg-type/+blkdebug/config/!str
(qmp) blockdev-add/arg-type/+blkdebug/image
(qmp) blockdev-add/arg-type/+blkdebug/image (recursion)
(qmp) blockdev-add/arg-type/+blkdebug/image/!str
(qmp) blockdev-add/arg-type/+blkdebug/inject-error

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>