databases/memcached: Update to 1.4.21

[koobs]

Summary

- Update to 1.4.21
- Remove doc patches (upstreamed)
- Remove unconditional CFLAGS
  * -fstack-protector is now a default
  * -I${LOCALBASE}/include casues SASL headers to be found even when
    --disable-sasl is set (SASL option disabled). Removal of these flags
    does not affect libevent header discovery
- While I'm here, whitespace alignment.

Test Plan

portlint: OK (two false positives)
porttest: OK
testport: OK (with and without SASL)
unittest: OK (see below)

All tests successful.
Files=50, Tests=7354, 267 wallclock secs ( 1.06 usr 0.47 sys + 3.52 cusr 2.74 csys = 7.80 CPU)
Result: PASS

[swills]

That's fine, go for it.

[koobs]

Committed: https://svnweb.freebsd.org/changeset/ports/374451