[LyX/master] Cmake: Allow test for X11 with QT5.6

[Kornel Benko]

commit 7a86fe3e0b70f944a2c99381ebf217609bf993e9
Author: Kornel Benko <kor...@lyx.org>
Date:   Mon May 30 08:22:15 2016 +0200

    Cmake: Allow test for X11 with QT5.6
    
    Used for key-test tests.

diff --git a/development/cmake/ConfigureChecks.cmake 
b/development/cmake/ConfigureChecks.cmake
index 825813b..2de915f 100644
--- a/development/cmake/ConfigureChecks.cmake
+++ b/development/cmake/ConfigureChecks.cmake
@@ -192,7 +192,10 @@ if(LYX_USE_QT MATCHES "QT5")
     get_target_property(_x11extra_link_libraries Qt5::X11Extras 
IMPORTED_LOCATION_${_x11extra_prop})
     set(CMAKE_REQUIRED_LIBRARIES ${_x11extra_link_libraries})
     set(CMAKE_REQUIRED_INCLUDES ${Qt5X11Extras_INCLUDE_DIRS})
-    set(CMAKE_REQUIRED_FLAGS ${Qt5X11Extras_EXECUTABLE_COMPILE_FLAGS})
+    set(CMAKE_REQUIRED_FLAGS "${Qt5X11Extras_EXECUTABLE_COMPILE_FLAGS} -fPIC 
-DQT_NO_VERSION_TAGGING")
+    #message(STATUS "CMAKE_REQUIRED_LIBRARIES = ${_x11extra_link_libraries}")
+    #message(STATUS "CMAKE_REQUIRED_INCLUDES = ${Qt5X11Extras_INCLUDE_DIRS}")
+    #message(STATUS "CMAKE_REQUIRED_FLAGS = ${CMAKE_REQUIRED_FLAGS}")
     check_cxx_source_compiles(
             "
             #include <QtX11Extras/QX11Info>