darray: annotate memset with -Wclass-mem-access acknowledgement
darray: annotate memset with -Wclass-mem-access acknowledgement

Yes, this stomps on the vtable pointers, but that's why we have the
placement new operator in ::allocate.

Signed-off-by: Steven Noonan <4068f0880b399410602d694b3cc711c8a8f4727e@uplinklabs.net>

tycho/crisscross,tycho/crisscross,tycho/crisscross