Update platforms/* with Eliot's fixes for 64-bit clean AsyncPlugin.
Update platforms/* with Eliot's fixes for 64-bit clean AsyncPlugin.

The platforms/unix changes are tested. The win32 and Mac OS changes are not tested but I believe them to be correct.
Not applicable to RiscOS.
Updates not applied to iOS.

@eliot - I changed the declarations in Cross to (void *) rather than long to reduce type casts in platforms/[unix|win32|Mac OS].

@esteban - I did not update platforms/iOS in SVN trunk. Please update declarations as needed.

@tim - no change required for RiscOS.



git-svn-id: http://squeakvm.org/svn/squeak/trunk@3178 fa1542d4-bde8-0310-ad64-8ed1123d492a

Former-commit-id: 55982481b07c41df485b88dff5a63920f92525d0
OpenSmalltalk/vm,timfel/squeakvm,timfel/squeakvm,OpenSmalltalk/vm,peteruhnak/pharo-vm,peteruhnak/pharo-vm,timfel/squeakvm,timfel/squeakvm,bencoman/pharo-vm,bencoman/pharo-vm,timfel/squeakvm,bencoman/pharo-vm,bencoman/pharo-vm,OpenSmalltalk/vm,timfel/squeakvm,bencoman/pharo-vm,bencoman/pharo-vm,peteruhnak/pharo-vm,peteruhnak/pharo-vm,OpenSmalltalk/vm,timfel/squeakvm,OpenSmalltalk/vm,bencoman/pharo-vm,bencoman/pharo-vm,OpenSmalltalk/vm,OpenSmalltalk/vm,OpenSmalltalk/vm,peteruhnak/pharo-vm,timfel/squeakvm,peteruhnak/pharo-vm,peteruhnak/pharo-vm,peteruhnak/pharo-vm,bencoman/pharo-vm