ipsec-tools: Revert "ipsec-tools: Flush the SA and SP list on service stop."

We don't want to flush the databases just because we bounce racoon. Really we
need a separate service for configuring the SPDs, similar to the setkey init
script in Debian's ipsec-tools package.

This reverts commit ca7436c695ce8c3e856d585b00eb262de7aa497e.

Signed-off-by: Noah Meyerhans <frodo@morgul.net>