[NativeAOT] Delete .NET SDK 6 support (#82568)

No longer needed

src/coreclr/nativeaot/BuildIntegration/Microsoft.DotNet.ILCompiler.SingleEntry.targets

@@ -32,34 +32,29 @@
   </PropertyGroup>
 
   <!-- If called via package instead of the SDK, update the runtime package version to match the build package -->
-  <ItemGroup Condition="'$(AotRuntimePackageLoadedViaSDK)' != 'true' and '$(NeedNativePublishSupportForSDK6)' != 'true'">
+  <ItemGroup Condition="'$(AotRuntimePackageLoadedViaSDK)' != 'true'">
     <KnownILCompilerPack Update="Microsoft.DotNet.ILCompiler">
       <ILCompilerPackVersion>$([System.IO.Path]::GetFileName($([System.IO.Path]::GetDirectoryName($([System.IO.Path]::GetDirectoryName($(ILCompilerTargetsPath)))))))</ILCompilerPackVersion>
     </KnownILCompilerPack>
   </ItemGroup>
 
   <!-- Generate a warning if the non-SDK path is used  -->
-  <Target Name="GenerateILCompilerExplicitPackageReferenceWarning" Condition="'$(SuppressGenerateILCompilerExplicitPackageReferenceWarning)' == '' and '$(AotRuntimePackageLoadedViaSDK)' != 'true' and '$(ILCompilerTargetsPath)' != ''  and '$(NeedNativePublishSupportForSDK6)' != 'true'" 
+  <Target Name="GenerateILCompilerExplicitPackageReferenceWarning" Condition="'$(SuppressGenerateILCompilerExplicitPackageReferenceWarning)' == '' and '$(AotRuntimePackageLoadedViaSDK)' != 'true' and '$(ILCompilerTargetsPath)' != ''"
       BeforeTargets="ImportRuntimeIlcPackageTarget">
     <Warning Condition="'%(PackageReference.Identity)' == 'Microsoft.DotNet.ILCompiler' And '%(PackageReference.IsImplicitlyDefined)' != 'true'"
              Text="Delete explicit 'Microsoft.DotNet.ILCompiler' package reference in your project file. Explicit 'Microsoft.DotNet.ILCompiler' package reference can run into version errors." />
   </Target>
 
   <!-- Locate the runtime package according to the current target runtime -->
-  <Target Name="ImportRuntimeIlcPackageTarget" Condition="'$(BuildingFrameworkLibrary)' != 'true' and ('$(PublishAot)' == 'true' or '$(NeedNativePublishSupportForSDK6)' == 'true') and $(IlcCalledViaPackage) == 'true'" DependsOnTargets="$(ImportRuntimeIlcPackageTargetDependsOn)" BeforeTargets="Publish">
-    <Error Condition="'@(ResolvedILCompilerPack)' == '' and '$(NeedNativePublishSupportForSDK6)' != 'true'" Text="The ResolvedILCompilerPack ItemGroup is required for target ImportRuntimeIlcPackageTarget" />
+  <Target Name="ImportRuntimeIlcPackageTarget" Condition="'$(BuildingFrameworkLibrary)' != 'true' and '$(PublishAot)' == 'true' and $(IlcCalledViaPackage) == 'true'" DependsOnTargets="$(ImportRuntimeIlcPackageTargetDependsOn)" BeforeTargets="Publish">
+    <Error Condition="'@(ResolvedILCompilerPack)' == ''" Text="The ResolvedILCompilerPack ItemGroup is required for target ImportRuntimeIlcPackageTarget" />
 
-    <PropertyGroup Condition="'$(NeedNativePublishSupportForSDK6)' != 'true'">
+    <PropertyGroup>
       <IlcHostPackagePath Condition="'@(ResolvedILCompilerPack)' == '$(IlcHostPackageName)'">@(ResolvedILCompilerPack->'%(PackageDirectory)')</IlcHostPackagePath>
       <RuntimePackagePath Condition="'@(ResolvedTargetILCompilerPack)' == '$(RuntimeIlcPackageName)'">@(ResolvedTargetILCompilerPack->'%(PackageDirectory)')</RuntimePackagePath>
       <RuntimePackagePath Condition="'@(ResolvedTargetILCompilerPack)' == ''">@(ResolvedILCompilerPack->'%(PackageDirectory)')</RuntimePackagePath>
     </PropertyGroup>
 
-    <PropertyGroup Condition="'$(NeedNativePublishSupportForSDK6)' == 'true'">
-      <RuntimePackagePath Condition="'%(PackageDefinitions.Name)' == '$(RuntimeIlcPackageName)'">%(PackageDefinitions.ResolvedPath)</RuntimePackagePath>
-      <IlcHostPackagePath Condition="'%(PackageDefinitions.Name)' == '$(IlcHostPackageName)'">%(PackageDefinitions.ResolvedPath)</IlcHostPackagePath>
-    </PropertyGroup>
-
   </Target>
 
   <Import Project="$(MSBuildThisFileDirectory)\Microsoft.NETCore.Native.targets" />