config: Give the option of disabling run as user/group

Leave "user/group" unset when explicitly configuring with
"--disable-user" / "--enable-user=no" and
"--disable-group" / "--enable-group=no"
This allows quagga to skip unsupported system calls such
as setuid() on certain platfroms.

Signed-off-by: Jafar Al-Gharaibeh <jafar@atcorp.com>
Signed-off-by: Jafar Al-Gharaibeh <jafar@atcorp.com>
Tested-by: NetDEF CI System <cisystem@netdef.org>
1 file changed