ntp: Revert "Disable ntpd stack gap. When ASLR with STACK GAP != 0 ntpd suffers SIGSEGV."
This reverts commit 55263180628a386ad38b4b6621919220b137f770 because the
underlying problem was fixed by 889b56c8cd84c9a9f2d9e3b019c154d6f14d9021.
MFC after: 1 month