fix invalid type error on systems with HAVE_VA_LIST_AS_ARRAY

[asmuth]

fixes #336

[kohler]

I'm confused. Where does HAVE_VA_LIST_AS_ARRAY come from? It's not something we define.

I'm worried that the type error actually represents a problem.

[kohler]

The CLICK_CHECK_ADDRESSABLE_VA_LIST configury step is supposed to detect this problem, and then leave HAVE_ADDRESSABLE_VA_LIST undefined.

[asmuth]

The problem came up a while back when trying to build click inside of a bitbake/yocto toolchain.

I did not realize there was already a check for this condition and added the HAVE_VA_LIST_AS_ARRAY ifdef (which seemed semi-standard, at least mozilla central and rpm use it) as a quick local patch and built with -DHAVE_VA_LIST_AS_ARRAY to work around the issue.

Of course if there already is a proper configure-time check for this, that should be used instead. I'll try debugging later/tomorrow why the CLICK_CHECK_ADDRESSABLE_VA_LIST did not work as intended inside of our cross toolchain.