lighttpd: security bump to version 1.14.51

lighttpd: security bump to version 1.14.51

Fixes the following security issues:

1.4.50:
[mod_alias] security: potential path traversal with specific configs
[core] security: use-after-free invalid Range req
[mod_alias] security: path traversal in mod_alias (in some use cases) (fixes #2898)
[core] security: use-after-free after invalid Range request (fixes #2899)

1.4.51:
[core,security] process headers after combining folded headers
[mod_userdir] security: skip username “.” and “..”

1.4.51 brings optional pam and wolfssl support.  Explicitly disable these
options for now.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>