COMP: allow Qt5 to compile on old kernels

SuperBuild/CMake/External_qt5.cmake

@@ -106,6 +106,10 @@ elseif(MSVC)
   set(QT5_SB_CONFIG "${QT5_SB_CONFIG} -mp")
 endif()
 
+if(LINUX AND USE_LOW_KERNEL_VERSION)
+  set(QT5_SB_CONFIG "${QT5_SB_CONFIG} -no-feature-getentropy -no-feature-renameat2")
+endif()
+
 if(WIN32)
   set(QT5_BIN_EXT ".exe")
   file(TO_NATIVE_PATH ${QT5_SB_SRC}/configure.bat QT5_CONFIGURE_SCRIPT)

SuperBuild/CMakeLists.txt

@@ -117,6 +117,13 @@ set(SUPERBUILD_OTB_VERSION "${SUPERBUILD_OTB_VERSION_MAJOR}.${SUPERBUILD_OTB_VER
 
 message("OTB version : ${SUPERBUILD_OTB_VERSION}")
 
+# Special setting for low kernel versions
+if(LINUX)
+  option(USE_LOW_KERNEL_VERSION "Try to keep the minimal kernel version as low as possible" OFF)
+endif()
+
+
+# Default install prefix
 get_filename_component(PARENT_OF_BINARY_DIR ${CMAKE_BINARY_DIR} PATH)
 if (CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT AND NOT USE_DEFAULT_INSTALL_PREFIX)
   set (CMAKE_INSTALL_PREFIX