[all] use explicit void parameter lists

This makes it a compile-time error to call a function that semantically
takes no parameters with a nonzero number of arguments.

Previously, such code would still compile, but risk blowing up the stack
if a compiler chose to use something other than caller-cleanup calling
conventions.

common/src/platform/windows/ivshmem.c

@@ -33,7 +33,7 @@ struct IVSHMEMInfo
   HANDLE handle;
 };
 
-void ivshmemOptionsInit()
+void ivshmemOptionsInit(void)
 {
   static struct Option options[] = {
     {