[Ada] Rename Returns_On_Secondary_Stack into Needs_Secondary_Stack
The Returns_On_Secondary_Stack predicate is a misnomer because it must be
invoked on a type and types do not return; as a matter of fact, the other
Returns_XXX predicates apply to functions.
gcc/ada/
* exp_ch6.adb (Caller_Known_Size): Invoke Needs_Secondary_Stack in
lieu of Returns_On_Secondary_Stack.
(Expand_Call_Helper): Likewise.
(Expand_Simple_Function_Return): Likewise.
(Needs_BIP_Alloc_Form): Likewise.
* exp_ch7.adb (Wrap_Transient_Declaration): Likewise.
* sem_res.adb (Resolve_Call): Likewise.
(Resolve_Entry_Call): Likewise.
* sem_util.ads (Returns_On_Secondary_Stack): Rename into...
(Needs_Secondary_Stack): ...this.
* sem_util.adb (Returns_On_Secondary_Stack): Rename into...
(Needs_Secondary_Stack): ...this.
* fe.h (Returns_On_Secondary_Stack): Delete.
(Needs_Secondary_Stack): New function.
* gcc-interface/decl.cc (gnat_to_gnu_subprog_type): Replace call
to Returns_On_Secondary_Stack with Needs_Secondary_Stack.