exclude building jit performance sub dir

Author: LakshanF

tests/src/dirs.proj

@@ -25,6 +25,7 @@
       <DisabledProjects Include="Common\external\external.csproj" />
       <DisabledProjects Include="Common\PerfHarness\PerfHarness.csproj" />
       <DisabledProjects Include="GC\Performance\Framework\GCPerfTestFramework.csproj" />
+      <DisabledProjects Include="JIT\Performance\**" />
       <DisabledProjects Include="Performance\Scenario\JitBench\unofficial_dotnet\JitBench.csproj" /> <!-- no official build support for SDK-style netcoreapp2.0 projects -->
       <DisabledProjects Include="Loader\classloader\generics\regressions\DD117522\Test.csproj" />
       <DisabledProjects Include="Loader\classloader\generics\GenericMethods\VSW491668.csproj" /> <!-- issue 5501 -->