Mark the package as nonshared to build it in the target specific build
step 1 of the build bots instead of the architecture generic build step
2. In the build step 2 it may be left out if we build it using a
different target.
Fixes: 24d6abe2d7cd ("firmware-utils: new package replacing otrx")
Link: https://github.com/openwrt/openwrt/pull/16031
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
4992946bc9