[PATCH] elf: Use C11 like atomics on _dl_mcount

[Wilco Dijkstra]

Hi Adhemerval,

-	      newfromidx = catomic_exchange_and_add (&fromidx, 1) + 1;
+	      newfromidx = atomic_fetch_and_acquire (&fromidx, 1) + 1;

I don't see how that could possibly work...

Btw is this trying to split my catomic patch into baby steps? Given these
are simple counters (not locks), you only need atomicity, so relaxed MO
is the obvious equivalent.

Cheers,
Wilco