meson: add feature flag for mime

mime builds and installs binaries, docs, units, etc. Add a
feature flag to make it easier to avoid shipping it.

meson_options.txt

@@ -213,6 +213,8 @@ option('machined', type : 'boolean',
        description : 'install the systemd-machined stack')
 option('measure', type : 'feature',
        description : 'install the systemd-measure tool')
+option('mime', type : 'feature',
+       description : 'install MIME type definitions')
 option('mountfsd', type : 'boolean',
        description : 'install the systemd-mountfsd stack')
 option('networkd', type : 'boolean',

mime/meson.build

@@ -1,3 +1,7 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
 
+if not get_option('mime').allowed()
+        subdir_done()
+endif
+
 install_data('io.systemd.xml', install_dir : mimepackagesdir)