package/procps-ng: needs gettext if locales

Fixes:
    http://autobuild.buildroot.net/results/88a/88a2c8907dce0e5abe0d544ce9a2875dfdcc9e7c/



Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>