Fix build failure when pointers smaller than integers.

Fix build failure when pointers smaller than integers.

	* expr.c (expand_builtin_setjmp): Store const1_rtx in target.
	(expand_builtin_longjmp): Abort if value isn't const1_rtx.
	Delete code storing value in static_chain_rtx.
	(expand_builtin, case BUILT_IN_LONGJMP): Pass NULL_RTX for target
	to second expand_expr call.

From-SVN: r20418