Have code and doc consistent.

The SSLRandomSeed  builtin, uses 128 bytes of stack, not 1kb of scoreboard data.
(r1832346 in trunk)

See PR 54752

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1832347 13f79535-47bb-0310-9956-ffa450edef68