head -r336568 and -r336570 appears to have made ci.freebsg.org's FreeBSD-head-amd64-gcc fail either than it had been (error: operand type 'struct <anonymous> *' is incompatible with argument 1 of '__atomic_fetch_add')

[John Baldwin]

I decided that it was better to fix our stdatomic.h, so I have a review
to do that at https://reviews.freebsd.org/D16585

-- 
John Baldwin