Don't #include within extern "C"

At least when building against trunk libstdc++ on Fedora 35 beta now, that
caused failures like

> In file included from ~/lo/core/libreofficekit/qa/unit/checkapi.cxx:18:
> In file included from ~/lo/core/workdir/UnpackedTarball/cppunit/include/cppunit/plugin/TestPlugIn.h:8:
> In file included from ~/lo/core/workdir/UnpackedTarball/cppunit/include/cppunit/plugin/PlugInParameters.h:8:
> In file included from ~/gcc/trunk/inst/lib/gcc/x86_64-pc-linux-gnu/12.0.0/../../../../include/c++/12.0.0/deque:70:
> In file included from ~/gcc/trunk/inst/lib/gcc/x86_64-pc-linux-gnu/12.0.0/../../../../include/c++/12.0.0/debug/deque:40:
> In file included from ~/gcc/trunk/inst/lib/gcc/x86_64-pc-linux-gnu/12.0.0/../../../../include/c++/12.0.0/debug/safe_sequence.h:35:
> In file included from ~/gcc/trunk/inst/lib/gcc/x86_64-pc-linux-gnu/12.0.0/../../../../include/c++/12.0.0/debug/safe_base.h:32:
> In file included from ~/gcc/trunk/inst/lib/gcc/x86_64-pc-linux-gnu/12.0.0/../../../../include/c++/12.0.0/ext/concurrence.h:34:
> ~/gcc/trunk/inst/lib/gcc/x86_64-pc-linux-gnu/12.0.0/../../../../include/c++/12.0.0/exception:83:8: error: declaration of 'terminate' has a different language linkage
>   void terminate() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__noreturn__));
>        ^
> ~/gcc/trunk/inst/lib/gcc/x86_64-pc-linux-gnu/12.0.0/../../../../include/c++/12.0.0/x86_64-pc-linux-gnu/bits/c++config.h:302:10: note: previous declaration is here
>     void terminate() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__noreturn__));
>          ^

Change-Id: I81cf87d13c16fd10ce3e2435509ab462852fce2f
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/123447
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

0 files changed, 0 insertions, 0 deletions