[calling conventions] Split 'set_context_sig_returns' back out into two functions, because attempting to cast a 'void *' to a 'va_list' gives a compile error on Ubuntu 64bit (error "cast specifies array type"). The varargs version of this function will be removed in the calling conventions branch.
[calling conventions] Split 'set_context_sig_returns' back out into two
functions, because attempting to cast a 'void *' to a 'va_list' gives a compile
error on Ubuntu 64bit (error "cast specifies array type"). The varargs version
of this function will be removed in the calling conventions branch.


git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@31676 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot