init.c: Do not adjust IP of an imported VMS exception of ia64.

init.c: Do not adjust IP of an imported VMS exception of ia64.

2007-04-20  Tristan Gingold  <gingold@adacore.com>
	    Olivier Hainque  <hainque@adacore.com>

	* init.c: Do not adjust IP of an imported VMS exception of ia64.
	LIB$STOP is called to raise an exception and the IP of the exception
	is the instruction right after the call.
	(__gnat_adjust_context_for_raise, AIX): Implement.
	(__gnat_error_handler, AIX): Accept SIGINFO related arguments and call
	 adjust_context_for_raise before Raise_From_Signal_Hanler.
	(__gnat_install_handler, AIX): Add SA_SIGINFO to the sa_flags, to ensure
	siginfo is passed to the handler, necessary to let the zcx propagation
	engine unwind past it.

From-SVN: r125428