Disable "Pointer is missing a nullability type specifier (_Nonnull, _Nullable, or _Null_unspecified)" warning

Old post but FWIW, I came across this warning in C++, when doing include of vk_mem_alloc.h, and got rid of it with a pragma:

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wnullability-completeness"
#include "vk_mem_alloc.h"
#pragma clang diagnostic pop