Document suggestion to use libffi for simple library bindings

Author: Grinnz

dist/ExtUtils-ParseXS/lib/perlxs.pod

@@ -79,6 +79,11 @@ Note: For some extensions, Dave Beazley's SWIG system may provide a
 significantly more convenient mechanism for creating the extension
 glue code.  See L<http://www.swig.org/> for more information.
 
+For simple bindings to C libraries as well as other machine code libraries,
+consider instead using the much simpler
+L<libffi|http://sourceware.org/libffi/> interface via CPAN modules like
+L<FFI::Platypus> or L<FFI::Raw>.
+
 =head2 On The Road
 
 Many of the examples which follow will concentrate on creating an interface

t/porting/known_pod_issues.dat

@@ -114,6 +114,8 @@ fchown(2)
 fcntl(2)
 fdopen(3)
 fetch(1)
+FFI::Platypus
+FFI::Raw
 fgrep(1)
 File::chdir
 File::Copy::Recursive