Eliminate C-style array declarations.
Remove nothrow from core.stdc.stdarg

Fix issue 13399
Merge pull request #939 from quickfur/issue13401

Eliminate C-style array declarations.
Merge pull request #940 from Dicebot/revert-745

[REG 2.066] Fix 13399 "va_arg is nothrow yet may throw "
When allocating a struct with "new", do not pass the pointer type info to the runtime, but the struct type info.
The fix also provides a small performance improvement as it no longer calls the virtual function TypeInfo.next() multiple times