message: fix rkcommon exported target information on windows
  A dependent project (OSPStudio) was trying to link the
  rkcommon*.cmake files and failing to compile. This change
  makes the glob more stringent on that platform so that
  it only picks up the library files.
diff: @@ -123,9 +123,15 @@ include(ospray_macros)
  if (OSPRAY_INSTALL_DEPENDENCIES)
  # Dependencies installed with OSPRay
  + if (WIN32)
  + file(GLOB_RECURSE EMBREE_LIBRARY ${LIBRARY_PATH_PREFIX}embree*.lib)
  + file(GLOB_RECURSE RKCOMMON_LIBRARY ${LIBRARY_PATH_PREFIX}rkcommon*.lib)
  + file(GLOB_RECURSE OPENVKL_LIBRARY ${LIBRARY_PATH_PREFIX}openvkl*.lib)
  + else()
  file(GLOB_RECURSE EMBREE_LIBRARY ${LIBRARY_PATH_PREFIX}embree*)
  file(GLOB_RECURSE RKCOMMON_LIBRARY ${LIBRARY_PATH_PREFIX}rkcommon*)
  file(GLOB_RECURSE OPENVKL_LIBRARY ${LIBRARY_PATH_PREFIX}openvkl*)
  + endif()
  else()
  # Find existing Dependencies on the machine
  if (NOT TARGET embree)
  