Primary output kind is already driven by the PackageItemKind definitions

This property value was useless for two reasons:
1 - The prior line was always setting $(PrimaryOutputKind) to a non-empty value,
    so it was never going to be effective.
2 - It duplicates the value for %(FrameworkSpecific) that is already part of the
    metadata for the corresponding PackageItemKind (Identity=Lib), so it was
    redundant.

Author: kzu

src/Build/NuGet.Build.Packaging.Tasks/NuGet.Build.Packaging.Inference.targets

@@ -19,8 +19,6 @@ Copyright (c) .NET Foundation. All rights reserved.
 
 		<!-- The Kind of primary output (build, symbols and doc) set if IncludeOutputsInPackage = true -->
 		<PrimaryOutputKind Condition="'$(PrimaryOutputKind)' == ''">Lib</PrimaryOutputKind>
-		<!-- Optionally can tweak whether the primary output is TF-specific or not. -->
-		<PrimaryOutputFrameworkSpecific Condition="'$(PrimaryOutputKind)' == ''">true</PrimaryOutputFrameworkSpecific>
 
 		<!-- Whether to include @(Content) items with CopyToOutputDirectory != '' in the package -->
 		<IncludeContentInPackage Condition="'$(IncludeContentInPackage)' == ''">true</IncludeContentInPackage>