[flang][OpenMP] Avoid unnecessary init loop, use constructor instead,… (#75482)

… NFC

SmallVector has a constructor that fills it with a number of copies of a
given value. Use it instead of a loop that does the same thing.

Author: kparzysz

flang/lib/Lower/OpenMP.cpp

@@ -2117,12 +2117,8 @@ static void createBodyOfOp(
     for (const Fortran::semantics::Symbol *arg : args)
       loopVarTypeSize = std::max(loopVarTypeSize, arg->GetUltimate().size());
     mlir::Type loopVarType = getLoopVarType(converter, loopVarTypeSize);
-    llvm::SmallVector<mlir::Type> tiv;
-    llvm::SmallVector<mlir::Location> locs;
-    for (int i = 0; i < (int)args.size(); i++) {
-      tiv.push_back(loopVarType);
-      locs.push_back(loc);
-    }
+    llvm::SmallVector<mlir::Type> tiv(args.size(), loopVarType);
+    llvm::SmallVector<mlir::Location> locs(args.size(), loc);
     firOpBuilder.createBlock(&op.getRegion(), {}, tiv, locs);
     int argIndex = 0;
     // The argument is not currently in memory, so make a temporary for the