Uses/iconv.mk: Set iconv-related CMake variables.

The way we deal with iconv in base and ports across different FreeBSD
releases is complicated: 9.x does not have iconv.h in base, 10.1 has it with
a different prototype for iconv(3) and later versions have the right
iconv(3) prototype. And, in some cases (USES=iconv:{translit,wchar_t}), we
must always use the libiconv port.

This is why there are so many checks in Uses/iconv.mk: we need to know the
situation we currently have in order to decide whether to pull iconv from
converters/libiconv, whether to just use its header (and pull the library
from base) or whether to use everything from base.

r384038 adjusted several CMake-based ports, but did so in a way that was not
very scalable and required a few intrusive patches to some ports. Most ports
that have both USES=cmake and USES=iconv use variations of FindIconv.cmake
that behave similarly. This change passes the header and library values we
really want to use to CMake using the most common variable names, bypassing
the calls to find_path() and find_library() that would sometimes end up
finding the wrong file. The few ports that use different variable names have
had their Makefiles adjusted (we manually pass the values we want via
CMAKE_ARGS).

Other changes:
- chinese/fcitx: Explicitly set LIBICONV_LIBC_HAS_ICONV_OPEN=OFF as we
  always want the version from ports because of USES=iconv:wchar_t.
- editors/calligra: Explicitly use iconv:translit because Kexi needs it.
- irc/weechat and irc/weechat-devel: The FindIconv.cmake patches could not
  be entirely removed because the check_library_exists() calls are wrong.
  Sent upstream: https://github.com/weechat/weechat/pull/513
- textproc/ctpp2: Use iconv:translit when the TRANSLITERATE option is used.

PORTREVISION has been bumped in editors/calligra and textproc/ctpp2 because
their dependency list has changed in 10.2 and later as the ports version is
always used now.

PR:		202798
Reviewed by:	antoine, tijl
Approved by:	portmgr (antoine)

- Remove const qualifier from iconv(3) to match POSIX: http://pubs.opengroup.org/onlinepubs/9699919799/functions/iconv.html - Patch iconv.h to expose more GNU extensions when LIBICONV_PLUG is defined because the base system iconv supports these extensions too. Add/remove patches to/from ports to call iconv with non-const arguments. This breaks some ports on FreeBSD 10 because base system iconv.h still has the const qualifier. Fix this by letting USES=iconv add a build dependency on converters/libiconv so ports can use its iconv.h (with LIBICONV_PLUG defined) instead of the base system iconv.h. This exposed some ports that link with libiconv when it is available instead of using libc iconv. In these cases one of the following changes has been made: - patch configure scripts to test for libc iconv first - add ac_cv_lib_iconv_libiconv=no or similar to CONFIGURE_ARGS to disable some configure tests - converters/wkhtmltopdf: this includes Qt4 so add a patch from devel/qt4 - lang/gcc5-aux: respect CFLAGS and friends during configure such that LIBICONV_PLUG is defined in the iconv test, also switch to external gettext - mail/gnarwl: replace patches with CPPFLAGS/LIBS - multimedia/ffmpeg2theora: remove iconv test from SConstruct and use ICONV_LIB in port Makefile instead, also fix a bug in subtitles.c - net-im/licq: finish conversion to cmake - net-mgmt/bandwidthd, net-mgmt/icinga, net-mgmt/nagios, net-mgmt/nagios4: don't need iconv - textproc/p5-XML-TinyXML: finish conversion to USES=perl5 Other changes: - databases/qdbm and slaves: respect CFLAGS and friends, also enable bzip2 and lzo support - games/ldmud: respect CFLAGS and friends - graphics/inventor: replace some patches with MAKE_ARGS/MAKE_ENV to respect CFLAGS and friends, also remove FreeBSD/alpha patch and add missing xorg dependencies PR: 199099 Exp-run by: antoine Approved by: portmgr (antoine)

- Bump PORTREVISION on all ports that depend on security/gnutls and adjust all ports that depend on security/gnutls3 - Update mail/anubis to version 4.2 which supports gnutls 3.x - Update mail/libvmime to a development snapshot (recommended by upstream developers) PR: 191274 Exp-run by: antoine Approved by: portmgr (antoine)