tree.def (SWITCH_EXPR): Change from 3 operand to 2 operand tree.

	* tree.def (SWITCH_EXPR): Change from 3 operand to 2 operand tree.
	Adjust comment.
	* tree.h (SWITCH_LABELS): Remove.
	* gimplify.c (gimplify_switch_expr): Don't test SWITCH_LABELS,
	assert SWITCH_BODY is non-NULL.
	* tree-pretty-print.c (dump_generic_node): Remove SWITCH_LABELS
	handling.
	* tree.c (block_may_fallthru): Always return true; for SWITCH_EXPR.
c/
	* c-typeck.c (c_start_case): Build SWITCH_EXPR using build2 instead
	of build3.
cp/
	* cp-gimplify.c (genericize_switch_stmt): Build SWITCH_EXPR using
	build2_loc instead of build3_loc.
ada/
	* gcc-interface/trans.c (Case_Statement_to_gnu): Build SWITCH_EXPR
	using build2 instead of build3.
jit/
	* jit-playback.c (add_switch): Build SWITCH_EXPR using build2 instead
	of build3.  Formatting fixes.  Adjust funciton comment.
fortran/
	* trans-decl.c (gfc_trans_entry_master_switch): Build SWITCH_EXPR
	using fold_build2_loc instead of fold_build3_loc.
	* trans-io.c (io_result): Likewise.
	* trans-stmt.c (gfc_trans_integer_select, gfc_trans_character_select):
	Likewise.
go/
	* go-gcc.cc (Gcc_backend::switch_statement): Build SWITCH_EXPR using
	build2_loc instead of build3_loc.
brig/
	* brigfrontend/brig-branch-inst-handler.cc
	(brig_branch_inst_handler::operator): Build SWITCH_EXPR using build2
	instead of build3.

From-SVN: r255192