(svn r18045) -Fix: GCC 4.5@HEAD not compiling OpenTTD anymore because of a "non-placement deallocation function [is] selected for placement delete", or in other words delete(void *, size_t) is 'magic'.
We implemented these delete(void *, size_t) operator functions because MSVC warned that "no matching operator delete found; memory will not be freed if initialization throws an exception" for new(size_t, size_t).
This disables MSVC warning about this because we do not use exceptions in the (constructors that use the) overridden allocation functions, as such they will never be called; delete(void *) remains necessary though.