* libltdl/lt__alloc.c, libltdl/lt_dlloader.c, libltdl/ltdl.c,
libltdl/slist.c, libltdl/libltdl/lt__alloc.h,
libltdl/libltdl/lt_error.h, libltdl/libltdl/slist.h,
libltdl/loaders/dld_link.c, libltdl/loaders/dlopen.c,
libltdl/loaders/dyld.c, libltdl/loaders/load_add_on.c,
libltdl/loaders/loadlibrary.c, libltdl/loaders/preopen.c,
libltdl/loaders/shl_load.c, tests/stresstest.at,
tests/testsuite.at, tests/f77demo/foo.h, tests/fcdemo/foo.h,
tests/mdemo/foo.h, tests/mdemo/foo1.c, tests/mdemo/foo2.c,
tests/mdemo/main.c: Allow sources to be compiled by a C++
compiler: Cast appropriately, add C linkage for `get_vtable'
functions, do not use C++ keyword `delete'.
