solenv/flatpak-manifest.in: Disable debug information again, for now

Merge in <https://github.com/flathub/org.libreoffice.LibreOffice/commit/
c6831b215070415a32669fbe63adfc4c36b5f568> "Disable debug information again, for
now", to bring repos back in sync.  If we want to keep this permanently,
--enable-symbols should instead be dropped from
distro-configs/LibreOfficeFlatpak.conf.

Change-Id: I656d77a446deecbc41ab25f05af7187dc544126c

solenv/flatpak-manifest.in

@@ -532,7 +532,7 @@
             ],
             "buildsystem": "simple",
             "build-commands": [
-                "./autogen.sh --prefix=/run/build/libreoffice/inst --with-distro=LibreOfficeFlatpak",
+                "./autogen.sh --prefix=/run/build/libreoffice/inst --with-distro=LibreOfficeFlatpak --disable-symbols",
                 "make",
                 "make distro-pack-install",
                 "make cmd cmd='$(SRCDIR)/solenv/bin/assemble-flatpak.sh'"