ethread.h return in void function

[Patrick Baggett]

I started compiling Erlang R14B on IRIX 6.5 with the native system compilers
and it stopped on line 760 of ethread.h, which is trying to return a value
in a function that is declared to return void. Simple fix is to just remove
"return". It looks like a copy-paste error.

Any chance this could get patched for the next release? Obviously it isn't a
high priority since it is a one-liner fix for a platform without any native
atomic ops (yet).

Patrick Baggett