s4:rpc_server/samr: Fix the O3 developer build

s4:rpc_server/samr: Fix the O3 developer build

Different gcc versions complain at different places.

I recently got these:

../source4/rpc_server/samr/dcesrv_samr.c: In function
‘dcesrv_samr_QueryDisplayInfo2’:
../source4/rpc_server/samr/dcesrv_samr.c:4117:2: error: ‘q.out.result.v’
may be used uninitialized in this function [-Werror=maybe-uninitialized]
  return result;
  ^
../source4/rpc_server/samr/dcesrv_samr.c: In function
‘dcesrv_samr_QueryDisplayInfo3’:
../source4/rpc_server/samr/dcesrv_samr.c:4151:2: error: ‘q.out.result.v’
may be used uninitialized in this function [-Werror=maybe-uninitialized]
  return result;
  ^
cc1: all warnings being treated as errors

../source4/rpc_server/samr/dcesrv_samr.c: In function
‘dcesrv_samr_QueryDisplayInfo3’:
../source4/rpc_server/samr/dcesrv_samr.c:4151:2: error: ‘q.out.result.v’
may be used uninitialized in this function [-Werror=maybe-uninitialized]
  return result;
  ^
In file included from ../source4/rpc_server/samr/dcesrv_samr.c:4447:0:
default/librpc/gen_ndr/ndr_samr_s.c: In function ‘samr__op_dispatch’:
default/librpc/gen_ndr/ndr_samr_s.c:597:18: error: ‘q.out.result.v’ may
be used uninitialized in this function [-Werror=maybe-uninitialized]
   r2->out.result = dcesrv_samr_QueryDisplayInfo2(dce_call, mem_ctx,
r2);
                  ^
cc1: all warnings being treated as errors

BUG: https://bugzilla.samba.org/show_bug.cgi?id=7113
BUG: https://bugzilla.samba.org/show_bug.cgi?id=11892

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>