For non-__HAVE_MD_TCB archs, p_tcb should be copied on fork.  Found by miod@
For non-__HAVE_MD_TCB archs, p_tcb should be copied on fork.  Found by miod@

p_oldmask and the core dump/debugger members don't need to be copied.
Pointed out by matthew@

ok miod@

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars