Fix rpath-link flag for SunPro C++ 5.11 on Linux

Commit 82c081ba (Fix rpath-link flag for SunPro C++ on Linux,
2009-07-13) taught CMake to pass '-rpath-link' because SunPro C++ 5.9
does not support '-Wl,'.  Now SunPro C++ 5.11 does not recognize the
option without using '-Wl,'.  Detect whether to use '-Wl,' based on the
output of "sunCC -flags".

Modules/Platform/Linux-SunPro-CXX.cmake

@@ -1,2 +1,9 @@
-SET(CMAKE_SHARED_LIBRARY_RPATH_LINK_CXX_FLAG "-rpath-link ")
+# Sun C++ 5.9 does not support -Wl, but Sun C++ 5.11 does not work without it.
+# Query the compiler flags to detect whether to use -Wl.
+execute_process(COMMAND ${CMAKE_CXX_COMPILER} -flags OUTPUT_VARIABLE _cxx_flags ERROR_VARIABLE _cxx_error)
+if("${_cxx_flags}" MATCHES "\n-W[^\n]*component")
+  set(CMAKE_SHARED_LIBRARY_RPATH_LINK_CXX_FLAG "-Wl,-rpath-link,")
+else()
+  set(CMAKE_SHARED_LIBRARY_RPATH_LINK_CXX_FLAG "-rpath-link ")
+endif()
 SET(CMAKE_EXE_EXPORTS_CXX_FLAG "--export-dynamic")