HashCode based on xxHash32 (dotnet/coreclr#14863)

* HashCode based on xxHash32

Works by maintaining the xxHash32 state variables (v1 -> v4, length) as well as a queue of values that fall outside of the block size (16 bytes/4 ints). The seed is initialized to random bytes.

Further details, unit tests and history: #25013

Signed-off-by: dotnet-bot-corefx-mirror <dotnet-bot@microsoft.com>

Author: jcdickinson

src/Common/src/System.Private.CoreLib/shared/System.Private.CoreLib.Shared.projitems

@@ -159,6 +159,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\UmAlQuraCalendar.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\UnicodeCategory.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Guid.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\HashCode.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\HResults.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\IAsyncResult.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\ICloneable.cs" />