smbd: check lp_load_printers before reload via NetShareEnum

smbd: check lp_load_printers before reload via NetShareEnum

api_RNetShareEnum() unconditionally attempts to reload printers via
delete_and_reload_printers(). Add a lp_load_printers() check to
obey smb.conf "load printers = off" settings.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14895

Reported-by: Nate Stuyvesant <nstuyvesant@gmail.com>
Signed-off-by: David Disseldorp <ddiss@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>
Autobuild-User(master): Andreas Schneider <asn@cryptomilk.org>
Autobuild-Date(master): Mon Nov  8 13:27:40 UTC 2021 on sn-devel-184