Fix msvc 2019 project files (internal linkage)

Closes #683

Signed-off-by: Chris Dickens <christopher.a.dickens@gmail.com>
diff --git a/msvc/xusb_2019.vcxproj b/msvc/xusb_2019.vcxproj
index 9bf5f50..adefefb 100644
--- a/msvc/xusb_2019.vcxproj
+++ b/msvc/xusb_2019.vcxproj
@@ -91,7 +91,7 @@
     <ClCompile Include="..\examples\xusb.c" />
   </ItemGroup>
   <ItemGroup>
-    <ProjectReference Include=".\libusb_static_2017.vcxproj">
+    <ProjectReference Include=".\libusb_static_2019.vcxproj">
       <Project>{349ee8f9-7d25-4909-aaf5-ff3fade72187}</Project>
       <ReferenceOutputAssembly>false</ReferenceOutputAssembly>
     </ProjectReference>