Merge bitcoin/bitcoin#34491: ci: add FreeBSD Clang cross job

65379bb8d0 ci: add FreeBSD cross CI job (fanquake)
f44191f163 depends: build qrencode for Freebsd (fanquake)
7f7018738e depends: FreeBSD cross with Clang (fanquake)
6464f14081 depends: disable inotify in Freebsd Qt build (fanquake)

Pull request description:

  Alternative to #33562, which was adding a native FreeBSD job; however that had issues with permissions/caching, as well as potential determinism issues. This adds a FreeBSD cross job using Linux and Clang.

  Would close #33438. The same changes here could also be used to produce FreeBSD binaries out of Guix.

ACKs for top commit:
  hebasto:
    ACK 65379bb8d0. I've cross-compiled on Ubuntu 25.10 for FreeBSD 14.4 and 15.0. The former binaries (`bitcoind`, `test_bitcoin` and `bitcoin-qt`) were tested on FreeBSD 14.4 locally.

Tree-SHA512: 52a3edaa56fe40ca901416cb9e1af04a84505526edfa7309bfa40024baa7d3b1a05303659553d9fbcf1f49d4e3d42b415a1e2523d448b22724d1415a49331259

.github/workflows/ci.yml

@@ -476,6 +476,12 @@ jobs:
             timeout-minutes: 120
             file-env: './ci/test/00_setup_env_mac_cross_intel.sh'
 
+          - name: 'FreeBSD Cross'
+            cirrus-runner: 'ghcr.io/cirruslabs/ubuntu-runner-amd64:24.04-md'
+            fallback-runner: 'ubuntu-24.04'
+            timeout-minutes: 120
+            file-env: './ci/test/00_setup_env_freebsd_cross.sh'
+
           - name: 'No wallet'
             cirrus-runner: 'ghcr.io/cirruslabs/ubuntu-runner-amd64:24.04-sm'
             fallback-runner: 'ubuntu-24.04'