Add alsactl utility

Allows saving and loading device state with the Flatpak version. The
Gnome 47 SDK uses alsa-lib 1.2.12 [1] via the Freedesktop.org SDK [2],
so we use that here as well.

[1] https://gitlab.gnome.org/search?search=alsa&nav_source=navbar&project_id=456&group_id=8&search_code=true&repository_ref=47.4
[2] https://gitlab.com/freedesktop-sdk/freedesktop-sdk/-/blob/release/24.08/elements/components/alsa-lib.bst?ref_type=heads

vu.b4.alsa-scarlett-gui.yml

@@ -17,6 +17,44 @@ finish-args:
   # Point to the firmware directory
   - --env=SCARLETT2_FIRMWARE_DIR=/app/lib/firmware/scarlett2
 modules:
+  - name: alsa-utils
+    sources:
+      - type: archive
+        url: https://www.alsa-project.org/files/pub/lib/alsa-lib-1.2.12.tar.bz2
+        sha256: 4868cd908627279da5a634f468701625be8cc251d84262c7e5b6a218391ad0d2
+        dest: .deps/alsa-lib
+      - type: archive
+        url: https://www.alsa-project.org/files/pub/utils/alsa-utils-1.2.12.tar.bz2
+        sha256: 98bc6677d0c0074006679051822324a0ab0879aea558a8f68b511780d30cd924
+    buildsystem: autotools
+    config-opts:
+      # We are only interested in alsactl
+      - --bindir=/app/null
+      - --with-udev-rules-dir=/app/null
+      - --with-systemdsystemunitdir=/app/null
+      # https://github.com/alsa-project/alsa-utils/issues/33
+      - --enable-alsa-topology
+      - --disable-alsaconf
+      - --disable-alsatest
+      - --disable-alsabat-backend-tiny
+      - --disable-alsamixer
+      - --disable-alsaloop
+      - --disable-nhlt
+      - --disable-xmlto
+      - --disable-rst2man
+      - --with-alsa-inc-prefix=.deps/alsa-lib/include
+    post-install:
+      - install -Dm755 /app/sbin/alsactl /app/bin/alsactl
+    cleanup:
+      - /lib/debug
+      - /lib/alsa-topology
+      - /null
+      - /sbin
+      - /share/alsa
+      - /share/locale
+      - /share/man
+      - /share/runtime
+      - /share/sounds
   - name: alsa-scarlett-gui
     buildsystem: simple
     build-commands: