remove make_Amounts:

* c++-17's class template type deduction can replace this function

src/ripple/app/paths/impl/BookStep.cpp

@@ -583,9 +583,9 @@ BookStep<TIn, TOut, TDerived>::forEachOffer (
                 prevStep_, offer, strandDst_, trOut);
 
         auto ofrAmt = offer.amount ();
-        auto stpAmt = make_Amounts (
+        TAmounts stpAmt{
             mulRatio (ofrAmt.in, ofrInRate, QUALITY_ONE, /*roundUp*/ true),
-            ofrAmt.out);
+            ofrAmt.out};
 
         // owner pays the transfer fee.
         auto ownerGives =

src/ripple/protocol/Quality.h

@@ -81,12 +81,6 @@ struct TAmounts
     Out out;
 };
 
-template<class In, class Out>
-TAmounts<In, Out> make_Amounts(In const& in, Out const& out)
-{
-    return TAmounts<In, Out>(in, out);
-}
-
 using Amounts = TAmounts<STAmount, STAmount>;
 
 template<class In, class Out>