Dear Release team,

[ Reason ]
Please unblock qbs to fix a FTBFS bug present in the current version in
testing (#1033430).

Build failure is caused by qt6-base 6.4.2+dfsg-4 upload after which qmake
and qdoc binaries are no longer in the same directory, which qbs assumed.
I fixed this by using a proper way to find qdoc binary (Qt6::qdoc target)
instead of relying on qmake. My fix was also accepted by upstream developers.

Also, the new version in sid includes upstream patch release 1.24.1 but it
contains just a couple of fixes:

$ git diff v1.24.0 v1.24.1 --stat
 CMakeLists.txt               | 4 +++-
 VERSION                      | 2 +-
 changelogs/changes-1.24.1.md | 9 +++++++++
 share/qbs/modules/cpp/iar.js | 2 ++
 4 files changed, 15 insertions(+), 2 deletions(-)

Finally, I marked some symbols as optional to fix FTBFS when building with
-O3 optimization level (as seen in Ubuntu ppc64el).

[ Impact ]
(What is the impact for the user if the unblock isn't granted?)

qbs will be auto-removed on May 7th, and that will cause the removal of
reverse dependencies: asyncfuture, dewalls, plotsauce, qmath3d.

[ Tests ]
(What automated or manual tests cover the affected code?)

We run the upstream test suite during build.

[ Risks ]
(Discussion of the risks involved. E.g. code is trivial or
complex, key package vs leaf package, alternatives available.)

I don't see any risks. The new version is in unstable for almost a month and
nobody complained.

[ Checklist ]
  [x] all changes are documented in the d/changelog
  [x] I reviewed all changes and I approve them
  [x] attach debdiff against the package in testing

[ Other info ]
(Anything else the release team should know.)

unblock qbs/1.24.1+dfsg-2

Unblocked.