Deprecate USE_GNU_READLINE.
Bump version for deprecated USE_GNU_READLINE.
Update to 3.2.2, with SunOS updates from Jörn Clausen.

* Version 3.2.2 (released 2013-07-14)

** libgnutls: Several optimizations in the related to packet processing
subsystems.

** libgnutls: DTLS replay detection can now be disabled (to be used
in certain transport layers like SCTP).

** libgnutls: Fixes in SRTP extension generation when MKI is being
used.

** libgnutls: Added ability to set hooks before or after sending or receiving
any handshake message with gnutls_handshake_set_hook_function().

** API and ABI modifications:
GNUTLS_NO_REPLAY_PROTECTION: Added
gnutls_certificate_set_trust_list: Added
gnutls_cipher_get_tag_size: Added
gnutls_record_overhead_size: Added
gnutls_est_record_overhead_size: Added
gnutls_handshake_set_hook_function: Added
gnutls_handshake_description_get_name: Added
gnutls_digest_list: Added
gnutls_digest_get_id: Added
gnutls_digest_get_name: Added
Updated security/gnutls to 3.2.2
Revert back to avoiding the system bison.  Whilst it is new enough to
satisfy the BISON_REQD check, it does not function correctly in the tools
environment when not called as /usr/bin/bison, as it is unable to find its
m4sugar.m4 without BISON_PKGDATADIR being set.

Whilst we could work around that in bison.mk I feel that's something of a
hack, and it is simpler and cleaner to just use the pkgsrc tool instead.