Fix condition for building runtime.native.System.IO.Ports (#34744)

Author: ericstj

src/libraries/pkg/runtime.native.System.IO.Ports/runtime.native.System.IO.Ports.builds

@@ -1,9 +1,9 @@
 <Project DefaultTargets="Build">
   <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.props))" />
 
-  <ItemGroup>
-    <!-- identity project, runtime specific projects are included through netcoreapp.rids.props -->
-    <Project Include="$(MSBuildProjectName).pkgproj" Condition="'$(TargetFramework)' == '$(NetCoreAppCurrent)'" />
+  <ItemGroup Condition="'$(BuildAllConfigurations)' == 'true'">
+    <!-- identity project built in AllConfigurations leg, runtime specific projects are included through netcoreapp.rids.props -->
+    <Project Include="$(MSBuildProjectName).pkgproj" />
   </ItemGroup>
 
   <Import Project="$([MSBuild]::GetPathOfFileAbove(dir.traversal.targets))" />