Xcode: Fix regression that automatically links libraries in source list

In commit e637744c51 (Xcode: Use "Link Binary With Libraries" to link
any library, 2019-07-10, v3.19.0-rc1~494^2~1) we accidentally added all
the library type files to "Link Binary With Libraries" build phase if
they were passed in as source files.  Revert that change as any actually
linked libraries will be added to that build phase later in the
`AddDependAndLinkInformation` call.

Fixes: #21361

Source/cmGlobalXCodeGenerator.cxx

@@ -1423,7 +1423,7 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
     cmGeneratorTarget::SourceFileFlags tsFlags =
       gtgt->GetTargetSourceFileFlags(sourceFile);
 
-    if (filetype && IsLibraryType(filetype->GetString())) {
+    if (filetype && filetype->GetString() == "compiled.mach-o.objfile") {
       if (sourceFile->GetObjectLibrary().empty()) {
         externalObjFiles.push_back(xsf);
       }
@@ -1591,7 +1591,7 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
     }
   }
 
-  // always create framework build phase
+  // Always create Link Binary With Libraries build phase
   cmXCodeObject* frameworkBuildPhase = nullptr;
   frameworkBuildPhase =
     this->CreateObject(cmXCodeObject::PBXFrameworksBuildPhase);
@@ -1600,6 +1600,7 @@ bool cmGlobalXCodeGenerator::CreateXCodeTarget(
                                     this->CreateString("2147483647"));
   buildFiles = this->CreateObject(cmXCodeObject::OBJECT_LIST);
   frameworkBuildPhase->AddAttribute("files", buildFiles);
+  // Add all collected .o files to this build phase
   for (auto& externalObjFile : externalObjFiles) {
     buildFiles->AddObject(externalObjFile);
   }