Migrate uStreamer directory permissions to the uStreamer Debian packa…

…ge (#14)

This change sets the correct permissions of the uStreamer directory
(i.e., /opt/ustreamer) using the uStreamer Debian package, replacing the
Ansible task.

Related: tiny-pilot/tinypilot#1467

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.lintianignore

@@ -2,3 +2,7 @@
 # clear guidance on where they *should* go. It's too much churn at this point to
 # change, so we're going to ignore this.
 dir-or-file-in-opt
+
+# Ignore this until we find a better way of setting permissions properly.
+# https://github.com/tiny-pilot/tinypilot/issues/1196
+recursive-privilege-change

debian/ustreamer.postinst

@@ -32,3 +32,6 @@ usermod \
   --append \
   --groups video \
   "${USTREAMER_USER}"
+
+# Assign ownership of the ustreamer dir to the ustreamer user and group.
+chown -R "${USTREAMER_USER}:${USTREAMER_GROUP}" /opt/ustreamer