Make the intermediate output path OS-specific for CoreCLR/Mono (#95797)

* Make the intermediate output path OS-specific

CoreLib is an OS-specific library. Using the same intermediate output path for
different OSes will lead to using stale artifacts such as ILLink descriptors.

* Set IntermediateOutputPath for Mono

---------

Co-authored-by: Alexander Köplinger <[email protected]>

Author: SingleAccretion

src/coreclr/Directory.Build.props

@@ -18,7 +18,7 @@
     <BaseIntermediateOutputPath Condition="'$(IsNativeAotProject)' != 'true'">$([MSBuild]::NormalizeDirectory('$(ArtifactsObjDir)', 'coreclr', '$(MSBuildProjectName)'))</BaseIntermediateOutputPath>
     <BaseIntermediateOutputPath Condition="'$(IsNativeAotProject)' == 'true'">$([MSBuild]::NormalizeDirectory('$(ArtifactsObjDir)', 'coreclr', 'nativeaot', '$(MSBuildProjectName)'))</BaseIntermediateOutputPath>
     <IntermediateOutputPath Condition="'$(PlatformName)' == 'AnyCPU'">$(BaseIntermediateOutputPath)$(Configuration)\</IntermediateOutputPath>
-    <IntermediateOutputPath Condition="'$(PlatformName)' != 'AnyCPU'">$(BaseIntermediateOutputPath)$(PlatformName)\$(Configuration)\</IntermediateOutputPath>
+    <IntermediateOutputPath Condition="'$(PlatformName)' != 'AnyCPU'">$(BaseIntermediateOutputPath)$(TargetOS).$(TargetArchitecture).$(Configuration)\</IntermediateOutputPath>
     <ProjectDir>$(MSBuildThisFileDirectory)</ProjectDir>
     <RuntimeBinDir>$([MSBuild]::NormalizeDirectory('$(ArtifactsBinDir)', 'coreclr', '$(TargetOS).$(TargetArchitecture).$(Configuration)'))</RuntimeBinDir>
 

src/mono/Directory.Build.props

@@ -8,7 +8,7 @@
   <PropertyGroup>
     <BaseIntermediateOutputPath>$([MSBuild]::NormalizeDirectory('$(ArtifactsObjDir)', 'mono', '$(MSBuildProjectName)'))</BaseIntermediateOutputPath>
     <IntermediateOutputPath Condition="'$(PlatformName)' == 'AnyCPU'">$(BaseIntermediateOutputPath)$(Configuration)\</IntermediateOutputPath>
-    <IntermediateOutputPath Condition="'$(PlatformName)' != 'AnyCPU'">$(BaseIntermediateOutputPath)$(PlatformName)\$(Configuration)\</IntermediateOutputPath>
+    <IntermediateOutputPath Condition="'$(PlatformName)' != 'AnyCPU'">$(BaseIntermediateOutputPath)$(TargetOS).$(TargetArchitecture).$(Configuration)\</IntermediateOutputPath>
   </PropertyGroup>
 
   <PropertyGroup>